1
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Li A, Li A, Zhou W. Low-voltage single-atom electron microscopy with carbon-based nanomaterials. Micron 2024; 186:103706. [PMID: 39216150 DOI: 10.1016/j.micron.2024.103706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2024] [Revised: 08/15/2024] [Accepted: 08/19/2024] [Indexed: 09/04/2024]
Abstract
The properties of materials are strongly correlated with their atomic scale structures. Achieving a comprehensive understanding of the atomic-scale structure-property relationship requires advancements of imaging and spectroscopy techniques. Aberration-corrected scanning transmission electron microscopy (STEM) has seen rapid development over the past decades and is now routinely employed for atomic-scale characterization. However, quantitative STEM imaging and spectroscopy analysis at the single-atom level is challenging due to the extremely weak signals generated from individual atom, thus imposing stringent requirements for analysis sensitivity. This review discusses the development and application of low-voltage STEM techniques with single-atom sensitivity, primarily based on recent research presented on an invited talk at the 5th 2D23 SALVE Symposium, including annular dark-field (ADF) imaging, functional imaging and electron energy-loss spectroscopy (EELS) analysis. Carbon-based nanomaterials were chosen as model systems for demonstrating the capabilities of single-atom STEM imaging and EELS analysis, due to their structural stability under low accelerating voltages and their rich physical and chemical properties. Moreover, this review summarizes recent advancements and applications of low-voltage single-atom STEM imaging and spectroscopy in the study of functional materials and discusses prospects for future developments.
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Affiliation(s)
- Aowen Li
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Ang Li
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Wu Zhou
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China.
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2
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Dai J, Sun Y, Liu Z, Zhang Y, Duan S, Wang R. Using In situ Transmission Electron Microscopy to Study Strong Metal-Support Interactions in Heterogeneous Catalysis. Angew Chem Int Ed Engl 2024; 63:e202409673. [PMID: 39052276 DOI: 10.1002/anie.202409673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Revised: 07/25/2024] [Accepted: 07/25/2024] [Indexed: 07/27/2024]
Abstract
Precisely controlling the microstructure of supported metal catalysts and regulating metal-support interactions at the atomic level are essential for achieving highly efficient heterogeneous catalysts. Strong metal-support interaction (SMSI) not only stabilizes metal nanoparticles and improves their resistance to sintering but also modulates the electrical interaction between metal species and the support, optimizing the catalytic activity and selectivity. Therefore, understating the formation mechanism of SMSI and its dynamic evolution during the chemical reaction at the atomic scale is crucial for guiding the structural design and performance optimization of supported metal catalysts. Recent advancements in in situ transmission electron microscopy (TEM) have shed new light on these complex phenomena, providing deeper insights into the SMSI dynamics. Here, the research progress of in situ TEM investigation on SMSI in heterogeneous catalysis is systematically reviewed, focusing on the formation dynamics, structural evolution during the catalytic reactions, and regulation methods of SMSI. The significant advantages of in situ TEM technologies for SMSI research are also highlighted. Moreover, the challenges and probable development paths of in situ TEM studies on the SMSI are also provided.
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Affiliation(s)
- Jie Dai
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, The State Key Laboratory for Advanced Metals and Materials, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yifei Sun
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, The State Key Laboratory for Advanced Metals and Materials, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Zhewei Liu
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, The State Key Laboratory for Advanced Metals and Materials, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yiyuan Zhang
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, The State Key Laboratory for Advanced Metals and Materials, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Sibin Duan
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, The State Key Laboratory for Advanced Metals and Materials, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Rongming Wang
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, The State Key Laboratory for Advanced Metals and Materials, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
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3
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Bao YF, Zhu MY, Zhao XJ, Chen HX, Wang X, Ren B. Nanoscale chemical characterization of materials and interfaces by tip-enhanced Raman spectroscopy. Chem Soc Rev 2024. [PMID: 39229965 DOI: 10.1039/d4cs00588k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/05/2024]
Abstract
Materials and their interfaces are the core for the development of a large variety of fields, including catalysis, energy storage and conversion. In this case, tip-enhanced Raman spectroscopy (TERS), which combines scanning probe microscopy with plasmon-enhanced Raman spectroscopy, is a powerful technique that can simultaneously obtain the morphological information and chemical fingerprint of target samples at nanometer spatial resolution. It is an ideal tool for the nanoscale chemical characterization of materials and interfaces, correlating their structures with chemical performances. In this review, we begin with a brief introduction to the nanoscale characterization of materials and interfaces, followed by a detailed discussion on the recent theoretical understanding and technical improvements of TERS, including the origin of enhancement, TERS instruments, TERS tips and the application of algorithms in TERS. Subsequently, we list the key experimental issues that need to be addressed to conduct successful TERS measurements. Next, we focus on the recent progress of TERS in the study of various materials, especially the novel low-dimensional materials, and the progresses of TERS in studying different interfaces, including both solid-gas and solid-liquid interfaces. Finally, we provide an outlook on the future developments of TERS in the study of materials and interfaces.
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Affiliation(s)
- Yi-Fan Bao
- Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
| | - Meng-Yuan Zhu
- Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
| | - Xiao-Jiao Zhao
- Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
| | - Hong-Xuan Chen
- Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
| | - Xiang Wang
- Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
- Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen 361005, China
| | - Bin Ren
- Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
- Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen 361005, China
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4
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Hoglund ER, Walker HA, Hussain K, Bao DL, Ni H, Mamun A, Baxter J, Caldwell JD, Khan A, Pantelides ST, Hopkins PE, Hachtel JA. Nonequivalent Atomic Vibrations at Interfaces in a Polar Superlattice. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2402925. [PMID: 38717326 DOI: 10.1002/adma.202402925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Revised: 04/17/2024] [Indexed: 06/15/2024]
Abstract
In heterostructures made from polar materials, e.g., AlN-GaN-AlN, the nonequivalence of the two interfaces is long recognized as a critical aspect of their electronic properties; in that, they host different 2D carrier gases. Interfaces play an important role in the vibrational properties of materials, where interface states enhance thermal conductivity and can generate unique infrared-optical activity. The nonequivalence of the corresponding interface atomic vibrations, however, is not investigated so far due to a lack of experimental techniques with both high spatial and high spectral resolution. Herein, the nonequivalence of AlN-(Al0.65Ga0.35)N and (Al0.65Ga0.35)N-AlN interface vibrations is experimentally demonstrated using monochromated electron energy-loss spectroscopy in the scanning transmission electron microscope (STEM-EELS) and density-functional-theory (DFT) calculations are employed to gain insights in the physical origins of observations. It is demonstrated that STEM-EELS possesses sensitivity to the displacement vector of the vibrational modes as well as the frequency, which is as critical to understanding vibrations as polarization in optical spectroscopies. The combination enables direct mapping of the nonequivalent interface phonons between materials with different phonon polarizations. The results demonstrate the capacity to carefully assess the vibrational properties of complex heterostructures where interface states dominate the functional properties.
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Affiliation(s)
- Eric R Hoglund
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
- Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA, 22904, USA
| | - Harrison A Walker
- Department of Physics and, Astronomy, Vanderbilt University, Nashville, TN, 37235, USA
- Interdisciplinary Materials Science Program, Vanderbilt University, Nashville, TN, 37235, USA
| | - Kamal Hussain
- Department of Electrical Engineering, University of South Carolina, Columbia, SC, 29208, USA
| | - De-Liang Bao
- Department of Physics and, Astronomy, Vanderbilt University, Nashville, TN, 37235, USA
| | - Haoyang Ni
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61820, USA
- Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, IL, 61820, USA
| | - Abdullah Mamun
- Interdisciplinary Materials Science Program, Vanderbilt University, Nashville, TN, 37235, USA
| | - Jefferey Baxter
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
| | - Joshua D Caldwell
- Department of Mechanical Engineering and Electrical Engineering, Vanderbilt University, Nashville, TN, 37235, USA
| | - Asif Khan
- Department of Electrical Engineering, University of South Carolina, Columbia, SC, 29208, USA
| | - Sokrates T Pantelides
- Department of Physics and, Astronomy, Vanderbilt University, Nashville, TN, 37235, USA
- Interdisciplinary Materials Science Program, Vanderbilt University, Nashville, TN, 37235, USA
- Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, 37235, USA
| | - Patrick E Hopkins
- Department of Materials Science and Engineering, University of Virginia, Charlottesville, VA, 22904, USA
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA, 22904, USA
- Department of Physics, University of Virginia, Charlottesville, VA, 22904, USA
| | - Jordan A Hachtel
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, 37830, USA
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5
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Li A, Zeiger PM, He Z, Xu M, Pennycook SJ, Rusz J, Zhou W. Systematic Absences of Optical Phonon Modes in Phonon Dispersion Measured by Electron Microscopy. PHYSICAL REVIEW LETTERS 2024; 133:046101. [PMID: 39121401 DOI: 10.1103/physrevlett.133.046101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Accepted: 06/10/2024] [Indexed: 08/11/2024]
Abstract
Phonon dispersion relations are widely used to elucidate the vibrational properties of materials. As an emerging technique, momentum-resolved vibrational spectroscopy in scanning transmission electron microscopy offers an unparalleled approach to explore q-dependent phonon behavior at local structures. In this study, we systematically investigate the phonon dispersion of monolayer graphene across several Brillouin zones (BZs) using momentum-resolved vibrational spectroscopy and find that the optical phonon signals vanish at the Γ points with indices (hk0) satisfying h+2k=3n (n denoted integers). Theoretical analysis reveals that the observed phenomena arise from the complete destructive interference of the scattered waves from different basis atoms. This observation, corroborated by the study of diamond, should be a general characteristic of materials composed of symmetrically equivalent pairs of the same elements. Moreover, our results emphasize the importance of multiple scattering in interpreting the vibrational signals in bulk materials. We demonstrate that the systematic absences and dynamic effects, which have not been much appreciated before, offer new insights into the experimental assessment of local vibrational properties of materials.
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6
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Shan S, Zhang Z, Volz S, Chen J. Phonon mode at interface and its impact on interfacial thermal transport. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:423001. [PMID: 38968932 DOI: 10.1088/1361-648x/ad5fd7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Accepted: 07/05/2024] [Indexed: 07/07/2024]
Abstract
Due to the minimization and integration of micro/nano-devices, the high density of interfaces becomes a significant challenge in various applications. Phonon modes at interface resulting from the mismatch between inhomogeneous functional counterparts are crucial for interfacial thermal transport and overall thermal management of micro/nano-devices, making it a topic of great research interest recently. Here, we comprehensively review the recent advances on the theoretical and experimental investigations of interfacial phonon mode and its impact on interfacial thermal transport. Firstly, we summarize the recent progresses of the theoretical and experimental characterization of interfacial phonon modes at various interfaces, along with the overview of the development of diverse methodologies. Then, the impact of interfacial phonon modes on interfacial thermal transport process are discussed from the normal modal decomposition and inelastic scattering mechanisms. Meanwhile, we examine various factors influencing the interfacial phonon modes and interfacial thermal transport, including temperature, interface roughness, interfacial mass gradient, interfacial disorder, and so on. Finally, an outlook is provided for future studies. This review provides a fundamental understanding of interfacial phonon modes and their impact on interfacial thermal transport, which would be beneficial for the exploration and optimization of thermal management in various micro/nano-devices with high density interfaces.
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Affiliation(s)
- Shuyue Shan
- Center for Phononics and Thermal Energy Science, China-EU Joint Lab for Nanophononics, MOE Key Laboratory of Advanced Micro-structured Materials, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Zhongwei Zhang
- Center for Phononics and Thermal Energy Science, China-EU Joint Lab for Nanophononics, MOE Key Laboratory of Advanced Micro-structured Materials, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Sebastian Volz
- Laboratory for Integrated Micro and Mechatronic Systems, CNRS-IIS UMI 2820, The University of Tokyo, Tokyo 153-8505, Japan
| | - Jie Chen
- Center for Phononics and Thermal Energy Science, China-EU Joint Lab for Nanophononics, MOE Key Laboratory of Advanced Micro-structured Materials, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
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7
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Yang J, Liu M, Wang T, Meng G, Wang Z, Guo C, Lin KT, Lin H, Jia B. Ultrafast Unidirectional On-Chip Heat Transfer. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2402575. [PMID: 38860359 DOI: 10.1002/smll.202402575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Revised: 05/23/2024] [Indexed: 06/12/2024]
Abstract
Effective and rapid heat transfer is critical to improving electronic components' performance and operational stability, particularly for highly integrated and miniaturized devices in complex scenarios. However, current thermal manipulation approaches, including the recent advancement in thermal metamaterials, cannot realize fast and unidirectional heat flow control. In addition, any defects in thermal conductive materials cause a significant decrease in thermal conductivity, severely degrading heat transfer performance. Here, the utilization of silicon-based valley photonic crystals (VPCs) is proposed and numerically demonstrated to facilitate ultrafast, unidirectional heat transfer through thermal radiation on a microscale. Utilizing the infrared wavelength region, the approach achieves a significant thermal rectification effect, ensuring continuous heat flow along designed paths with high transmission efficiency. Remarkably, the process is unaffected by temperature gradients due to the unidirectional property, maintaining transmission directionality. Furthermore, the VPCs' inherent robustness affords defect-immune heat transfer, overcoming the limitations of traditional conduction methods that inevitably cause device heating, performance degradation, and energy waste. The design is fully CMOS compatible, thus will find broad applications, particularly for integrated optoelectronic devices.
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Affiliation(s)
- Junbo Yang
- School of Mechanical, Electrical and Information Engineering, Shandong University, Weihai, 264209, China
- Suzhou Research Institute, Shandong University, 388 Ruoshui Road, Suzhou, 215123, China
- School of Science, RMIT University, 124 La Trobe Street, Melbourne, Victoria, 3000, Australia
| | - Miao Liu
- School of Mechanical, Electrical and Information Engineering, Shandong University, Weihai, 264209, China
- Suzhou Research Institute, Shandong University, 388 Ruoshui Road, Suzhou, 215123, China
- School of Science, RMIT University, 124 La Trobe Street, Melbourne, Victoria, 3000, Australia
| | - Tanhe Wang
- School of Mechanical, Electrical and Information Engineering, Shandong University, Weihai, 264209, China
- Suzhou Research Institute, Shandong University, 388 Ruoshui Road, Suzhou, 215123, China
| | - Ge Meng
- School of Mechanical, Electrical and Information Engineering, Shandong University, Weihai, 264209, China
- Suzhou Research Institute, Shandong University, 388 Ruoshui Road, Suzhou, 215123, China
| | - Zhaoyang Wang
- School of Mechanical, Electrical and Information Engineering, Shandong University, Weihai, 264209, China
- Suzhou Research Institute, Shandong University, 388 Ruoshui Road, Suzhou, 215123, China
| | - Chunsheng Guo
- School of Mechanical, Electrical and Information Engineering, Shandong University, Weihai, 264209, China
- Suzhou Research Institute, Shandong University, 388 Ruoshui Road, Suzhou, 215123, China
| | - Keng-Te Lin
- School of Science, RMIT University, 124 La Trobe Street, Melbourne, Victoria, 3000, Australia
| | - Han Lin
- School of Science, RMIT University, 124 La Trobe Street, Melbourne, Victoria, 3000, Australia
| | - Baohua Jia
- School of Science, RMIT University, 124 La Trobe Street, Melbourne, Victoria, 3000, Australia
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8
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Di Giulio V, Akerboom E, Polman A, García de Abajo FJ. Toward Optimum Coupling between Free Electrons and Confined Optical Modes. ACS NANO 2024; 18:14255-14275. [PMID: 38775711 PMCID: PMC11155252 DOI: 10.1021/acsnano.3c12977] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 04/10/2024] [Accepted: 04/25/2024] [Indexed: 06/05/2024]
Abstract
Free electrons are excellent tools to probe and manipulate nanoscale optical fields with emerging applications in ultrafast spectromicroscopy and quantum metrology. However, advances in this field are hindered by the small probability associated with the excitation of single optical modes by individual free electrons. Here, we theoretically investigate the scaling properties of the electron-driven excitation probability for a wide variety of optical modes including plasmons in metallic nanostructures and Mie resonances in dielectric cavities, spanning a broad spectral range that extends from the ultraviolet to the infrared region. The highest probabilities for the direct generation of three-dimensionally confined modes are observed at low electron and mode energies in small structures, with order-unity (∼100%) coupling demanding the use of <100 eV electrons interacting with eV polaritons confined down to tens of nanometers in space. Electronic transitions in artificial atoms also emerge as practical systems to realize strong coupling to few-eV free electrons. In contrast, conventional dielectric cavities reach a maximum probability in the few-percent range. In addition, we show that waveguide modes can be generated with higher-than-unity efficiency by phase-matched interaction with grazing electrons, suggesting a practical method to create multiple excitations of a localized optical mode by an individual electron through funneling the so-generated propagating photons into a confining cavity─an alternative approach to direct electron-cavity interaction. Our work provides a roadmap to optimize electron-photon coupling with potential applications in electron spectromicroscopy as well as nonlinear and quantum optics at the nanoscale.
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Affiliation(s)
- Valerio Di Giulio
- The
Barcelona Institute of Science and Technology, Institut de Ciencies Fotoniques-ICFO, 08860 Castelldefels (Barcelona), Spain
| | - Evelijn Akerboom
- Center
for Nanophotonics, NWO-Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Albert Polman
- Center
for Nanophotonics, NWO-Institute AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - F. Javier García de Abajo
- The
Barcelona Institute of Science and Technology, Institut de Ciencies Fotoniques-ICFO, 08860 Castelldefels (Barcelona), Spain
- ICREA-Institució
Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys 23, 08010 Barcelona, Spain
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9
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Yang L, Yue S, Tao Y, Qiao S, Li H, Dai Z, Song B, Chen Y, Du J, Li D, Gao P. Suppressed thermal transport in silicon nanoribbons by inhomogeneous strain. Nature 2024; 629:1021-1026. [PMID: 38750362 DOI: 10.1038/s41586-024-07390-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 04/05/2024] [Indexed: 05/31/2024]
Abstract
Nanoscale structures can produce extreme strain that enables unprecedented material properties, such as tailored electronic bandgap1-5, elevated superconducting temperature6,7 and enhanced electrocatalytic activity8,9. While uniform strains are known to elicit limited effects on heat flow10-15, the impact of inhomogeneous strains has remained elusive owing to the coexistence of interfaces16-20 and defects21-23. Here we address this gap by introducing inhomogeneous strain through bending individual silicon nanoribbons on a custom-fabricated microdevice and measuring its effect on thermal transport while characterizing the strain-dependent vibrational spectra with sub-nanometre resolution. Our results show that a strain gradient of 0.112% per nanometre could lead to a drastic thermal conductivity reduction of 34 ± 5%, in clear contrast to the nearly constant values measured under uniform strains10,12,14,15. We further map the local lattice vibrational spectra using electron energy-loss spectroscopy, which reveals phonon peak shifts of several millielectron-volts along the strain gradient. This unique phonon spectra broadening effect intensifies phonon scattering and substantially impedes thermal transport, as evidenced by first-principles calculations. Our work uncovers a crucial piece of the long-standing puzzle of lattice dynamics under inhomogeneous strain, which is absent under uniform strain and eludes conventional understanding.
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Affiliation(s)
- Lin Yang
- Department of Advanced Manufacturing and Robotics, College of Engineering, Peking University, Beijing, People's Republic of China.
| | - Shengying Yue
- Laboratory for Multiscale Mechanics and Medical Science, State Key Laboratory for Strength and Vibration of Mechanical Structures, School of Aerospace, Xi'an Jiaotong University, Xi'an, People's Republic of China
| | - Yi Tao
- School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, People's Republic of China
| | - Shuo Qiao
- Department of Advanced Manufacturing and Robotics, College of Engineering, Peking University, Beijing, People's Republic of China
| | - Hang Li
- Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, People's Republic of China
| | - Zhaohe Dai
- Department of Mechanics and Engineering Science, College of Engineering, Peking University, Beijing, People's Republic of China
| | - Bai Song
- Department of Advanced Manufacturing and Robotics, College of Engineering, Peking University, Beijing, People's Republic of China
- Department of Energy and Resources Engineering, College of Engineering, Peking University, Beijing, People's Republic of China
| | - Yunfei Chen
- School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing, People's Republic of China
| | - Jinlong Du
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, People's Republic of China.
| | - Deyu Li
- Department of Mechanical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Peng Gao
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, People's Republic of China.
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, People's Republic of China.
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10
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Liu B, Allison W, Peng B, Avidor N, Monserrat B, Jardine AP. Distinguishing Quasiparticle-Phonon Interactions by Ultrahigh-Resolution Lifetime Measurements. PHYSICAL REVIEW LETTERS 2024; 132:176202. [PMID: 38728725 DOI: 10.1103/physrevlett.132.176202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 01/22/2024] [Accepted: 03/22/2024] [Indexed: 05/12/2024]
Abstract
We present a determination of quasiparticle-phonon interaction strengths at surfaces through measurements of phonon spectra with ultrahigh energy resolution. The lifetimes of low energy surface phonons on a pristine Ru(0001) surface were determined over a wide range of temperatures and an analysis of the temperature dependence enables us to attribute separate contributions from electron-phonon interactions, phonon-phonon interactions, and defect-phonon interactions. Strong electron-phonon interactions are evident at all temperatures and we show they dominate over phonon-phonon interactions below 400 K.
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Affiliation(s)
- Boyao Liu
- SMF Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - William Allison
- SMF Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Bo Peng
- TCM Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Nadav Avidor
- SMF Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Bartomeu Monserrat
- TCM Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
| | - Andrew P Jardine
- SMF Group, Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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11
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Shi R, Li Q, Xu X, Han B, Zhu R, Liu F, Qi R, Zhang X, Du J, Chen J, Yu D, Zhu X, Guo J, Gao P. Atomic-scale observation of localized phonons at FeSe/SrTiO 3 interface. Nat Commun 2024; 15:3418. [PMID: 38653990 DOI: 10.1038/s41467-024-47688-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Accepted: 04/03/2024] [Indexed: 04/25/2024] Open
Abstract
In single unit-cell FeSe grown on SrTiO3, the superconductivity transition temperature features a significant enhancement. Local phonon modes at the interface associated with electron-phonon coupling may play an important role in the interface-induced enhancement. However, such phonon modes have eluded direct experimental observations. The complicated atomic structure of the interface brings challenges to obtain the accurate structure-phonon relation knowledge. Here, we achieve direct characterizations of atomic structure and phonon modes at the FeSe/SrTiO3 interface with atomically resolved imaging and electron energy loss spectroscopy in an electron microscope. We find several phonon modes highly localized (~1.3 nm) at the unique double layer Ti-O terminated interface, one of which (~ 83 meV) engages in strong interactions with the electrons in FeSe based on ab initio calculations. This finding of the localized interfacial phonon associated with strong electron-phonon coupling provides new insights into understanding the origin of superconductivity enhancement at the FeSe/SrTiO3 interface.
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Affiliation(s)
- Ruochen Shi
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
| | - Qize Li
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
- Department of Physics, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Xiaofeng Xu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bo Han
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
| | - Ruixue Zhu
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
| | - Fachen Liu
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
- Academy for Advanced Interdisciplinary Studies, Peking University, Beijing, 100871, China
| | - Ruishi Qi
- Department of Physics, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Xiaowen Zhang
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
| | - Jinlong Du
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
| | - Ji Chen
- Institute of Condensed Matter and Material Physics, Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing, 100871, China
- Collaborative Innovation Center of Quantum Matter, Beijing, 100871, China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing, 100871, China
| | - Dapeng Yu
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China
- Shenzhen Institute for Quantum Science and Engineering (SIQSE), Southern University of Science and Technology, Shenzhen, 518055, China
- Hefei National Laboratory, 230088, Hefei, China
| | - Xuetao Zhu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Jiandong Guo
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Peng Gao
- International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China.
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, 100871, China.
- Collaborative Innovation Center of Quantum Matter, Beijing, 100871, China.
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing, 100871, China.
- Hefei National Laboratory, 230088, Hefei, China.
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12
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Asghar U, Qamar MA, Hakami O, Ali SK, Imran M, Farhan A, Parveen H, Sharma M. Recent Advances in Carbon Nanotube Utilization in Perovskite Solar Cells: A Review. MICROMACHINES 2024; 15:529. [PMID: 38675340 PMCID: PMC11051801 DOI: 10.3390/mi15040529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2024] [Revised: 03/25/2024] [Accepted: 04/11/2024] [Indexed: 04/28/2024]
Abstract
Due to their exceptional optoelectronic properties, halide perovskites have emerged as prominent materials for the light-absorbing layer in various optoelectronic devices. However, to increase device performance for wider adoption, it is essential to find innovative solutions. One promising solution is incorporating carbon nanotubes (CNTs), which have shown remarkable versatility and efficacy. In these devices, CNTs serve multiple functions, including providing conducting substrates and electrodes and improving charge extraction and transport. The next iteration of photovoltaic devices, metal halide perovskite solar cells (PSCs), holds immense promise. Despite significant progress, achieving optimal efficiency, stability, and affordability simultaneously remains a challenge, and overcoming these obstacles requires the development of novel materials known as CNTs, which, owing to their remarkable electrical, optical, and mechanical properties, have garnered considerable attention as potential materials for highly efficient PSCs. Incorporating CNTs into perovskite solar cells offers versatility, enabling improvements in device performance and longevity while catering to diverse applications. This article provides an in-depth exploration of recent advancements in carbon nanotube technology and its integration into perovskite solar cells, serving as transparent conductive electrodes, charge transporters, interlayers, hole-transporting materials, and back electrodes. Additionally, we highlighted key challenges and offered insights for future enhancements in perovskite solar cells leveraging CNTs.
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Affiliation(s)
- Usman Asghar
- Center of Excellence in Solid State Physics, University of the Punjab, Lahore 54590, Pakistan;
| | - Muhammad Azam Qamar
- Department of Chemistry, School of Science, University of Management and Technology, Lahore 54770, Pakistan
| | - Othman Hakami
- Department of Physical Sciences, Chemistry Division, College of Science, Jazan University, P.O. Box 114, Jazan 45142, Saudi Arabia;
| | - Syed Kashif Ali
- Department of Physical Sciences, Chemistry Division, College of Science, Jazan University, P.O. Box 114, Jazan 45142, Saudi Arabia;
- Nanotechnology Research Unit, College of Science, Jazan University, P.O. Box 114, Jazan 45142, Saudi Arabia
| | - Mohd Imran
- Department of Chemical Engineering, College of Engineering, Jazan University, P.O. Box 706, Jazan 45142, Saudi Arabia;
| | - Ahmad Farhan
- Department of Chemistry, University of Agriculture Faisalabad, Faisalabad 38000, Pakistan;
| | - Humaira Parveen
- Department of Chemistry, Faculty of Science, University of Tabuk, Tabuk 71491, Saudi Arabia;
| | - Mukul Sharma
- Environment and Nature Research Centre, Jazan University, P.O. Box 114, Jazan 45142, Saudi Arabia;
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13
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Yan J, Shi R, Wei J, Li Y, Qi R, Wu M, Li X, Feng B, Gao P, Shibata N, Ikuhara Y. Nanoscale Localized Phonons at Al 2O 3 Grain Boundaries. NANO LETTERS 2024; 24:3323-3330. [PMID: 38466652 DOI: 10.1021/acs.nanolett.3c04149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Nanoscale defects like grain boundaries (GBs) would introduce local phonon modes and affect the bulk materials' thermal, electrical, optical, and mechanical properties. It is highly desirable to correlate the phonon modes and atomic arrangements for individual defects to precisely understand the structure-property relation. Here we investigated the localized phonon modes of Al2O3 GBs by combination of the vibrational electron energy loss spectroscopy (EELS) in scanning transmission electron microscope and density functional perturbation theory (DFPT). The differences between GB and bulk obtained from the vibrational EELS show that the GB exhibited more active vibration at the energy range of <50 meV and >80 meV, and further DFPT results proved the wide distribution of bond lengths at GB are the main factor for the emergence of local phonon modes. This research provides insights into the phonon-defect relation and would be of importance in the design and application of polycrystalline materials.
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Affiliation(s)
- Jingyuan Yan
- Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Ruochen Shi
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
- International Center for Quantum Materials, Peking University, Beijing 100871, China
| | - Jiake Wei
- Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Yuehui Li
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
- International Center for Quantum Materials, Peking University, Beijing 100871, China
| | - Ruishi Qi
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
- International Center for Quantum Materials, Peking University, Beijing 100871, China
- Department of Physics, University of California at Berkeley, Berkeley 94720, California, United States
| | - Mei Wu
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
- International Center for Quantum Materials, Peking University, Beijing 100871, China
| | - Xiaomei Li
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
- School of Integrated Circuits, East China Normal University, Shanghai 200241, China
| | - Bin Feng
- Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan
- PRESTO, Japan Science and Technology Agency, Kawaguchi 332-0012, Japan
| | - Peng Gao
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
- International Center for Quantum Materials, Peking University, Beijing 100871, China
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing 100871, China
| | - Naoya Shibata
- Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan
- Nanostructures Research Laboratory, Japan Fine Ceramics Center, Nagoya 456-8587, Japan
| | - Yuichi Ikuhara
- Institute of Engineering Innovation, The University of Tokyo, Tokyo 113-8656, Japan
- Nanostructures Research Laboratory, Japan Fine Ceramics Center, Nagoya 456-8587, Japan
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14
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Sun X, Suriyage M, Khan AR, Gao M, Zhao J, Liu B, Hasan MM, Rahman S, Chen RS, Lam PK, Lu Y. Twisted van der Waals Quantum Materials: Fundamentals, Tunability, and Applications. Chem Rev 2024; 124:1992-2079. [PMID: 38335114 DOI: 10.1021/acs.chemrev.3c00627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2024]
Abstract
Twisted van der Waals (vdW) quantum materials have emerged as a rapidly developing field of two-dimensional (2D) semiconductors. These materials establish a new central research area and provide a promising platform for studying quantum phenomena and investigating the engineering of novel optoelectronic properties such as single photon emission, nonlinear optical response, magnon physics, and topological superconductivity. These captivating electronic and optical properties result from, and can be tailored by, the interlayer coupling using moiré patterns formed by vertically stacking atomic layers with controlled angle misorientation or lattice mismatch. Their outstanding properties and the high degree of tunability position them as compelling building blocks for both compact quantum-enabled devices and classical optoelectronics. This paper offers a comprehensive review of recent advancements in the understanding and manipulation of twisted van der Waals structures and presents a survey of the state-of-the-art research on moiré superlattices, encompassing interdisciplinary interests. It delves into fundamental theories, synthesis and fabrication, and visualization techniques, and the wide range of novel physical phenomena exhibited by these structures, with a focus on their potential for practical device integration in applications ranging from quantum information to biosensors, and including classical optoelectronics such as modulators, light emitting diodes, lasers, and photodetectors. It highlights the unique ability of moiré superlattices to connect multiple disciplines, covering chemistry, electronics, optics, photonics, magnetism, topological and quantum physics. This comprehensive review provides a valuable resource for researchers interested in moiré superlattices, shedding light on their fundamental characteristics and their potential for transformative applications in various fields.
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Affiliation(s)
- Xueqian Sun
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Manuka Suriyage
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Ahmed Raza Khan
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Department of Industrial and Manufacturing Engineering, University of Engineering and Technology (Rachna College Campus), Gujranwala, Lahore 54700, Pakistan
| | - Mingyuan Gao
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- College of Engineering and Technology, Southwest University, Chongqing 400716, China
| | - Jie Zhao
- Department of Quantum Science & Technology, Research School of Physics, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Australian Research Council Centre of Excellence for Quantum Computation and Communication Technology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Boqing Liu
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Md Mehedi Hasan
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Sharidya Rahman
- Department of Materials Science and Engineering, Monash University, Clayton, Victoria 3800, Australia
- ARC Centre of Excellence in Exciton Science, Monash University, Clayton, Victoria 3800, Australia
| | - Ruo-Si Chen
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Ping Koy Lam
- Department of Quantum Science & Technology, Research School of Physics, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Institute of Materials Research and Engineering (IMRE), Agency for Science, Technology and Research (A*STAR), 2 Fusionopolis Way, Innovis #08-03, Singapore 138634, Republic of Singapore
- Australian Research Council Centre of Excellence for Quantum Computation and Communication Technology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Yuerui Lu
- School of Engineering, College of Engineering and Computer Science, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Australian Research Council Centre of Excellence for Quantum Computation and Communication Technology, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
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15
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Liu B, Kelsall J, Ward DJ, Jardine AP. Experimental Characterization of Defect-Induced Phonon Lifetime Shortening. PHYSICAL REVIEW LETTERS 2024; 132:056202. [PMID: 38364135 DOI: 10.1103/physrevlett.132.056202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/18/2023] [Accepted: 12/15/2023] [Indexed: 02/18/2024]
Abstract
We present the first direct experimental measurement of defect-induced lifetime shortening of acoustic surface phonons. Defects are found to contribute a temperature-independent component to the linewidths of Rayleigh wave phonons on a Ni(111) surface. We also characterized the increase in phonon scattering with both surface defect density and phonon wave vector. A quantitative estimate of the scattering rate between phonon modes and surface line defects is extracted from the experimental data for the first time.
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Affiliation(s)
- Boyao Liu
- Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Jack Kelsall
- Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - David J Ward
- Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
| | - Andrew P Jardine
- Cavendish Laboratory, University of Cambridge, 19 J J Thomson Avenue, Cambridge CB3 0HE, United Kingdom
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16
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Kuang X, Pantaleón Peralta PA, Angel Silva-Guillén J, Yuan S, Guinea F, Zhan Z. Optical properties and plasmons in moiré structures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2024; 36:173001. [PMID: 38232397 DOI: 10.1088/1361-648x/ad1f8c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 01/17/2024] [Indexed: 01/19/2024]
Abstract
The discoveries of numerous exciting phenomena in twisted bilayer graphene (TBG) are stimulating significant investigations on moiré structures that possess a tunable moiré potential. Optical response can provide insights into the electronic structures and transport phenomena of non-twisted and twisted moiré structures. In this article, we review both experimental and theoretical studies of optical properties such as optical conductivity, dielectric function, non-linear optical response, and plasmons in moiré structures composed of graphene, hexagonal boron nitride (hBN), and/or transition metal dichalcogenides. Firstly, a comprehensive introduction to the widely employed methodology on optical properties is presented. After, moiré potential induced optical conductivity and plasmons in non-twisted structures are reviewed, such as single layer graphene-hBN, bilayer graphene-hBN and graphene-metal moiré heterostructures. Next, recent investigations of twist-angle dependent optical response and plasmons are addressed in twisted moiré structures. Additionally, we discuss how optical properties and plasmons could contribute to the understanding of the many-body effects and superconductivity observed in moiré structures.
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Affiliation(s)
- Xueheng Kuang
- Yangtze Delta Industrial Innovation Center of Quantum Science and Technology, Suzhou 215000, People's Republic of China
| | | | - Jose Angel Silva-Guillén
- Instituto Madrileño de Estudios Avanzados, IMDEA Nanociencia, Calle Faraday 9, 28049 Madrid, Spain
| | - Shengjun Yuan
- Key Laboratory of Artificial Micro- and Nano-structures of the Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072, People's Republic of China
- Wuhan Institute of Quantum Technology, Wuhan 430206, People's Republic of China
| | - Francisco Guinea
- Instituto Madrileño de Estudios Avanzados, IMDEA Nanociencia, Calle Faraday 9, 28049 Madrid, Spain
- Donostia International Physics Center, Paseo Manuel de Lardizábal 4, 20018 San Sebastián, Spain
| | - Zhen Zhan
- Instituto Madrileño de Estudios Avanzados, IMDEA Nanociencia, Calle Faraday 9, 28049 Madrid, Spain
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17
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Bao DL, Xu M, Li AW, Su G, Zhou W, Pantelides ST. Phonon vortices at heavy impurities in two-dimensional materials. NANOSCALE HORIZONS 2024; 9:248-253. [PMID: 38091005 DOI: 10.1039/d3nh00433c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2024]
Abstract
The advent of monochromated electron energy-loss spectroscopy has enabled atomic-resolution vibrational spectroscopy, which triggered interest in spatially localized or quasi-localized vibrational modes in materials. Here we report the discovery of phonon vortices at heavy impurities in two-dimensional materials. We use density-functional-theory calculations for two configurations of Si impurities in graphene, Si-C3 and Si-C4, to examine atom-projected phonon densities of states and display the atomic-displacement patterns for select modes that are dominated by impurity displacements. The vortices are driven by large displacements of the impurities, and reflect local symmetries. Similar vortices are found at phosphorus impurities in hexagonal boron nitride, suggesting that they may be a feature of heavy impurities in crystalline materials. Phonon vortices at defects are expected to play a role in thermal conductivity and other properties.
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Affiliation(s)
- De-Liang Bao
- Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235, USA.
| | - Mingquan Xu
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of the Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Ao-Wen Li
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of the Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Gang Su
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of the Chinese Academy of Sciences, Beijing 100049, P. R. China
- Kavli Institute for Theoretical Sciences, University of the Chinese Academy of Sciences, Beijing, P. R. China
| | - Wu Zhou
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of the Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Sokrates T Pantelides
- Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235, USA.
- Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, Tennessee 37235, USA
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18
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Hoffman AJ, Temmerman W, Campbell E, Damin AA, Lezcano-Gonzalez I, Beale AM, Bordiga S, Hofkens J, Van Speybroeck V. A Critical Assessment on Calculating Vibrational Spectra in Nanostructured Materials. J Chem Theory Comput 2024; 20:513-531. [PMID: 38157404 PMCID: PMC10809426 DOI: 10.1021/acs.jctc.3c00942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 11/30/2023] [Accepted: 12/05/2023] [Indexed: 01/03/2024]
Abstract
Vibrational spectroscopy is an omnipresent spectroscopic technique to characterize functional nanostructured materials such as zeolites, metal-organic frameworks (MOFs), and metal-halide perovskites (MHPs). The resulting experimental spectra are usually complex, with both low-frequency framework modes and high-frequency functional group vibrations. Therefore, theoretically calculated spectra are often an essential element to elucidate the vibrational fingerprint. In principle, there are two possible approaches to calculate vibrational spectra: (i) a static approach that approximates the potential energy surface (PES) as a set of independent harmonic oscillators and (ii) a dynamic approach that explicitly samples the PES around equilibrium by integrating Newton's equations of motions. The dynamic approach considers anharmonic and temperature effects and provides a more genuine representation of materials at true operating conditions; however, such simulations come at a substantially increased computational cost. This is certainly true when forces and energy evaluations are performed at the quantum mechanical level. Molecular dynamics (MD) techniques have become more established within the field of computational chemistry. Yet, for the prediction of infrared (IR) and Raman spectra of nanostructured materials, their usage has been less explored and remain restricted to some isolated successes. Therefore, it is currently not a priori clear which methodology should be used to accurately predict vibrational spectra for a given system. A comprehensive comparative study between various theoretical methods and experimental spectra for a broad set of nanostructured materials is so far lacking. To fill this gap, we herein present a concise overview on which methodology is suited to accurately predict vibrational spectra for a broad range of nanostructured materials and formulate a series of theoretical guidelines to this purpose. To this end, four different case studies are considered, each treating a particular material aspect, namely breathing in flexible MOFs, characterization of defects in the rigid MOF UiO-66, anharmonic vibrations in the metal-halide perovskite CsPbBr3, and guest adsorption on the pores of the zeolite H-SSZ-13. For all four materials, in their guest- and defect-free state and at sufficiently low temperatures, both the static and dynamic approach yield qualitatively similar spectra in agreement with experimental results. When the temperature is increased, the harmonic approximation starts to fail for CsPbBr3 due to the presence of anharmonic phonon modes. Also, the spectroscopic fingerprints of defects and guest species are insufficiently well predicted by a simple harmonic model. Both phenomena flatten the potential energy surface (PES), which facilitates the transitions between metastable states, necessitating dynamic sampling. On the basis of the four case studies treated in this Review, we can propose the following theoretical guidelines to simulate accurate vibrational spectra of functional solid-state materials: (i) For nanostructured crystalline framework materials at low temperature, insights into the lattice dynamics can be obtained using a static approach relying on a few points on the PES and an independent set of harmonic oscillators. (ii) When the material is evaluated at higher temperatures or when additional complexity enters the system, e.g., strong anharmonicity, defects, or guest species, the harmonic regime breaks down and dynamic sampling is required for a correct prediction of the phonon spectrum. These guidelines and their illustrations for prototype material classes can help experimental and theoretical researchers to enhance the knowledge obtained from a lattice dynamics study.
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Affiliation(s)
| | - Wim Temmerman
- Center
for Molecular Modeling, Ghent University, 9000 Ghent, Belgium
| | - Emma Campbell
- Cardiff
Catalysis Institute, Cardiff University, Cardiff CF10 3AT, United Kingdom
- Research
Complex at Harwell, Didcot OX11 0FA, United
Kingdom
| | | | - Ines Lezcano-Gonzalez
- Research
Complex at Harwell, Didcot OX11 0FA, United
Kingdom
- Department
of Chemistry, University College London, London WC1E 6BT, United Kingdom
| | - Andrew M. Beale
- Research
Complex at Harwell, Didcot OX11 0FA, United
Kingdom
- Department
of Chemistry, University College London, London WC1E 6BT, United Kingdom
| | - Silvia Bordiga
- Department
of Chemistry, University of Turin, 10124 Turin, Italy
| | - Johan Hofkens
- Department
of Chemistry, KU Leuven, 3000 Leuven, Belgium
- Max Planck
Institute for Polymer Research, 55128 Mainz, Germany
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19
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Moradifar P, Liu Y, Shi J, Siukola Thurston ML, Utzat H, van Driel TB, Lindenberg AM, Dionne JA. Accelerating Quantum Materials Development with Advances in Transmission Electron Microscopy. Chem Rev 2023. [PMID: 37979189 DOI: 10.1021/acs.chemrev.2c00917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2023]
Abstract
Quantum materials are driving a technology revolution in sensing, communication, and computing, while simultaneously testing many core theories of the past century. Materials such as topological insulators, complex oxides, superconductors, quantum dots, color center-hosting semiconductors, and other types of strongly correlated materials can exhibit exotic properties such as edge conductivity, multiferroicity, magnetoresistance, superconductivity, single photon emission, and optical-spin locking. These emergent properties arise and depend strongly on the material's detailed atomic-scale structure, including atomic defects, dopants, and lattice stacking. In this review, we describe how progress in the field of electron microscopy (EM), including in situ and in operando EM, can accelerate advances in quantum materials and quantum excitations. We begin by describing fundamental EM principles and operation modes. We then discuss various EM methods such as (i) EM spectroscopies, including electron energy loss spectroscopy (EELS), cathodoluminescence (CL), and electron energy gain spectroscopy (EEGS); (ii) four-dimensional scanning transmission electron microscopy (4D-STEM); (iii) dynamic and ultrafast EM (UEM); (iv) complementary ultrafast spectroscopies (UED, XFEL); and (v) atomic electron tomography (AET). We describe how these methods could inform structure-function relations in quantum materials down to the picometer scale and femtosecond time resolution, and how they enable precision positioning of atomic defects and high-resolution manipulation of quantum materials. For each method, we also describe existing limitations to solve open quantum mechanical questions, and how they might be addressed to accelerate progress. Among numerous notable results, our review highlights how EM is enabling identification of the 3D structure of quantum defects; measuring reversible and metastable dynamics of quantum excitations; mapping exciton states and single photon emission; measuring nanoscale thermal transport and coupled excitation dynamics; and measuring the internal electric field and charge density distribution of quantum heterointerfaces- all at the quantum materials' intrinsic atomic and near atomic-length scale. We conclude by describing open challenges for the future, including achieving stable sample holders for ultralow temperature (below 10K) atomic-scale spatial resolution, stable spectrometers that enable meV energy resolution, and high-resolution, dynamic mapping of magnetic and spin fields. With atomic manipulation and ultrafast characterization enabled by EM, quantum materials will be poised to integrate into many of the sustainable and energy-efficient technologies needed for the 21st century.
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Affiliation(s)
- Parivash Moradifar
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
| | - Yin Liu
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Jiaojian Shi
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road MS69, Menlo Park, California 94025, United States
| | | | - Hendrik Utzat
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States
| | - Tim B van Driel
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, United States
| | - Aaron M Lindenberg
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road MS69, Menlo Park, California 94025, United States
| | - Jennifer A Dionne
- Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, United States
- Department of Radiology, Stanford University, Stanford, California 94305, United States
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20
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Su L, Jia S, Ren J, Lu X, Guo SW, Guo P, Cai Z, Lu D, Niu M, Zhuang L, Peng K, Wang H. Strong yet flexible ceramic aerogel. Nat Commun 2023; 14:7057. [PMID: 37923727 PMCID: PMC10624812 DOI: 10.1038/s41467-023-42703-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 10/19/2023] [Indexed: 11/06/2023] Open
Abstract
Ceramic aerogels are highly efficient, lightweight, and chemically stable thermal insulation materials but their application is hindered by their brittleness and low strength. Flexible nanostructure-assembled compressible aerogels have been developed to overcome the brittleness but they still show low strength, leading to insufficient load-bearing capacity. Here we designed and fabricated a laminated SiC-SiOx nanowire aerogel that exhibits reversible compressibility, recoverable buckling deformation, ductile tensile deformation, and simultaneous high strength of up to an order of magnitude larger than other ceramic aerogels. The aerogel also shows good thermal stability ranging from -196 °C in liquid nitrogen to above 1200 °C in butane blow torch, and good thermal insulation performance with a thermal conductivity of 39.3 ± 0.4 mW m-1 K-1. These integrated properties make the aerogel a promising candidate for mechanically robust and highly efficient flexible thermal insulation materials.
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Affiliation(s)
- Lei Su
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Shuhai Jia
- School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an, 710049, China.
| | - Junqiang Ren
- State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metal, Department of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Xuefeng Lu
- State Key Laboratory of Advanced Processing and Recycling of Non-ferrous Metal, Department of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou, 730050, China
| | - Sheng-Wu Guo
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Pengfei Guo
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Zhixin Cai
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - De Lu
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Min Niu
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Lei Zhuang
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Kang Peng
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China
| | - Hongjie Wang
- State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, 710049, China.
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21
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Wu M, Shi R, Qi R, Li Y, Du J, Gao P. Four-dimensional electron energy-loss spectroscopy. Ultramicroscopy 2023; 253:113818. [PMID: 37544270 DOI: 10.1016/j.ultramic.2023.113818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 06/20/2023] [Accepted: 07/25/2023] [Indexed: 08/08/2023]
Abstract
Recent advances in scanning transmission electron microscopy have enabled atomic-scale focused, coherent, and monochromatic electron probes, achieving nanoscale spatial resolution, meV energy resolution, sufficient momentum resolution, and a wide energy detection range in electron energy-loss spectroscopy (EELS). A four-dimensional EELS (4D-EELS) dataset can be recorded with a slot aperture selecting the specific momentum direction in the diffraction plane and the beam scanning in two spatial dimensions. In this paper, the basic principle of the 4D-EELS technique and a few examples of its application are presented. In addition to parallelly acquired dispersion with energy down to a lattice vibration scale, it can map the real space variation of any EELS spectrum features with a specific momentum transfer and energy loss to study various locally inhomogeneous scattering processes. Furthermore, simple mathematical combinations associating the spectra at different momenta are feasible from the 4D dataset, e.g., the efficient acquisition of a reliable electron magnetic circular dichroism (EMCD) signal is demonstrated. This 4D-EELS technique provides new opportunities to probe the local dispersion and related physical properties at the nanoscale.
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Affiliation(s)
- Mei Wu
- International Center for Quantum Materials, Peking University, Beijing 100871, China; Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Ruochen Shi
- International Center for Quantum Materials, Peking University, Beijing 100871, China; Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Ruishi Qi
- Department of Physics, University of California at Berkeley, Berkeley 94720, United States
| | - Yuehui Li
- International Center for Quantum Materials, Peking University, Beijing 100871, China; Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Jinlong Du
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China
| | - Peng Gao
- International Center for Quantum Materials, Peking University, Beijing 100871, China; Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871, China; Collaborative Innovation Center of Quantum Matter, Beijing 100871, China; Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing 100871, China.
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22
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Hou W, Wei Y. Evaluating the resolution of conventional optical microscopes through point spread function measurement. iScience 2023; 26:107976. [PMID: 37822495 PMCID: PMC10562796 DOI: 10.1016/j.isci.2023.107976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023] Open
Abstract
In the imaging process of conventional optical microscopy, the primary factor hindering microscope resolution is the energy diffusion of incident light, most directly described by the point spread function (PSF). Therefore, accurate calculation and measurement of PSF are essential for evaluating and enhancing imaging resolution. Currently, there are various methods to obtain PSFs, each with different advantages and disadvantages suitable for different scenarios. To provide a comprehensive analysis of PSF-obtaining methods, this study classifies them into four categories based on different acquisition principles and analyzes their advantages and disadvantages, starting from the propagation property of light in optical physics. Finally, two PSF-obtaining methods are proposed based on mathematical modeling and deep learning, demonstrating their effectiveness through experimental results. This study compares and analyzes these results, highlighting the practical applications of image deblurring.
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Affiliation(s)
- Weihan Hou
- Key Laboratory of Intelligent Computing in Medical Image, Ministry of Education, College of Computer Science and Engineering, Northeastern University, Wenhua Street 3, Shenyang 110819, China
| | - Yangjie Wei
- Key Laboratory of Intelligent Computing in Medical Image, Ministry of Education, College of Computer Science and Engineering, Northeastern University, Wenhua Street 3, Shenyang 110819, China
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23
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Guo Y, Lupini AR. Automatic and Quantitative Measurement of Spectrometer Aberrations. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:1671-1681. [PMID: 37670369 DOI: 10.1093/micmic/ozad084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Revised: 06/16/2023] [Accepted: 07/29/2023] [Indexed: 09/07/2023]
Abstract
The performance of electron energy loss spectrometers can often be limited by their electron optical aberrations. Due to recent developments in high energy resolution and momentum-resolved electron energy loss spectroscopy (EELS), there is renewed interest in optimizing the performance of such spectrometers. For example, the "ω - q" mode of momentum-resolved EELS, which uses a small convergence angle and requires aligning diffraction spots with the slot aperture, presents a challenge in the realignments of the spectrometer required by the adjustment of the projection lenses. Automated and robust alignment can greatly benefit such a process. The first step toward this goal is automatic and quantitative measurement of spectrometer aberrations. We demonstrate the measurement of geometric aberrations and distortions in EELS within a monochromated scanning transmission electron microscope (STEM). To better understand the results, we present a wave mechanical simulation of the experiment. Using the measured aberration and distortion coefficients as inputs to the simulation, we find a good match between the simulation and experiment, verifying formulae used in the simulation. From verified simulations with known aberration coefficients, we can assess the accuracy of measurements. Understanding the errors and inaccuracies in the procedure can guide further progress in aberration measurement and correction for new spectrometer developments.
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Affiliation(s)
- Yueming Guo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831, USA
| | - Andrew R Lupini
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831, USA
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24
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Yin K, Shi L, Ma X, Zhong Y, Li M, He X. Thermal Conductivity of 3C/4H-SiC Nanowires by Molecular Dynamics Simulation. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2196. [PMID: 37570514 PMCID: PMC10421163 DOI: 10.3390/nano13152196] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023]
Abstract
Silicon carbide (SiC) is a promising material for thermoelectric power generation. The characterization of thermal transport properties is essential to understanding their applications in thermoelectric devices. The existence of stacking faults, which originate from the "wrong" stacking sequences of Si-C bilayers, is a general feature of SiC. However, the effects of stacking faults on the thermal properties of SiC are not well understood. In this study, we evaluated the accuracy of Tersoff, MEAM, and GW potentials in describing the thermal transport of SiC. Additionally, the thermal conductivity of 3C/4H-SiC nanowires was investigated using non-equilibrium molecular dynamics simulations (NEMD). Our results show that thermal conductivity exhibits an increase and then saturation as the total lengths of the 3C/4H-SiC nanowires vary from 23.9 nm to 95.6 nm, showing the size effect of molecular dynamics simulations of the thermal conductivity. There is a minimum thermal conductivity, as a function of uniform period length, of the 3C/4H-SiC nanowires. However, the thermal conductivities of nanowires weakly depend on the gradient period lengths and the ratio of 3C/4H. Additionally, the thermal conductivity of 3C/4H-SiC nanowires decreases continuously from compressive strain to tensile strain. The reduction in thermal conductivity suggests that 3C/4H-SiC nanowires have potential applications in advanced thermoelectric devices. Our study provides insights into the thermal transport properties of SiC nanowires and can guide the development of SiC-based thermoelectric materials.
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Affiliation(s)
- Kaili Yin
- Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin 150080, China
| | - Liping Shi
- Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin 150080, China
| | - Xiaoliang Ma
- Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin 150080, China
| | - Yesheng Zhong
- Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin 150080, China
| | - Mingwei Li
- School of Material Science and Engineering, Harbin Institute of Technology, Harbin 150001, China
| | - Xiaodong He
- Center for Composite Materials and Structures, Harbin Institute of Technology, Harbin 150080, China
- Shenzhen STRONG Advanced Materials Research Institute Co., Ltd., Shenzhen 518000, China
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25
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Wang Y, Yang S, Crozier PA. Spectroscopic Observation and Modeling of Photonic Modes in CeO2 Nanostructures. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:1307-1314. [PMID: 37488821 DOI: 10.1093/micmic/ozad059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 04/24/2023] [Accepted: 05/02/2023] [Indexed: 07/26/2023]
Abstract
Photonic modes in dielectric nanostructures, e.g., wide gap semiconductor like CeO2 (ceria), have the potential for various applications such as information transmission and sensing technology. To fully understand the properties of such phenomenon at the nanoscale, electron energy-loss spectroscopy (EELS) in a scanning transmission electron microscope was employed to detect and explore photonic modes in well-defined ceria nanocubes. To facilitate the interpretation of the observations, EELS simulations were performed with finite-element methods. The simulations allow the electric and magnetic field distributions associated with different modes to be determined. A simple analytical eigenfunction model was also used to estimate the energy of the photonic modes. In addition, by comparing various spectra taken at different location relative to the cube, the effect of the surrounding environment on the modes could be sensed. This work gives a high-resolution description of the photonic modes' properties in nanostructures, while demonstrating the advantage of EELS in characterizing optical phenomena locally.
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Affiliation(s)
- Yifan Wang
- School for Engineering of Matter, Transport & Energy, Arizona State University, 501 E. Tyler Mall, Tempe, AZ 85287, USA
| | - Shize Yang
- Eyring Materials Center, Arizona State University, 1001 S McAllister Ave, Tempe, AZ 85287-8301, USA
| | - Peter A Crozier
- School for Engineering of Matter, Transport & Energy, Arizona State University, 501 E. Tyler Mall, Tempe, AZ 85287, USA
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26
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Haas B, Boland TM, Elsässer C, Singh AK, March K, Barthel J, Koch CT, Rez P. Atomic Resolution Mapping of Localized Phonon Modes in Silicon Grain Boundaries. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:618-619. [PMID: 37613300 DOI: 10.1093/micmic/ozad067.300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Benedikt Haas
- Department of Physics & IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Tara M Boland
- School for Engineering of Matter Transport and Energy, Arizona State University, Tempe, AZ, United States
| | | | - Arunima K Singh
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Katia March
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris, France
| | - Juri Barthel
- Ernst Ruska-Centre (ER-C 2), Forschungszentrum Jülich; Jülich, Germany
| | - Christoph T Koch
- Department of Physics & IRIS Adlershof, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Peter Rez
- Department of Physics, Arizona State University, Tempe, AZ, United States
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27
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Xu M, Bao DL, Li A, Gao M, Meng D, Li A, Du S, Su G, Pennycook SJ, Pantelides ST, Zhou W. Single-atom Vibrational Spectroscopy with Chemical Bonding Sensitivity. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:616-617. [PMID: 37613043 DOI: 10.1093/micmic/ozad067.299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Mingquan Xu
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - De-Liang Bao
- Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA
- Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Aowen Li
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Meng Gao
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Dongqian Meng
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Ang Li
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Shixuan Du
- Institute of Physics, Chinese Academy of Sciences, Beijing, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Gang Su
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
- Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Stephen J Pennycook
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
| | - Sokrates T Pantelides
- Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
- Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA
| | - Wu Zhou
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, China
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28
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Wang Y, Yang S, Fischer A, Grotjohn T, Ponce F, Crozier PA. Exploring the Effect of Diffraction Conditions on Off-Axis Phonon EELS. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:653-655. [PMID: 37613386 DOI: 10.1093/micmic/ozad067.320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Yifan Wang
- School for Engineering of Matter, Transport & Energy, Arizona State University, Tempe, AZ, United States
| | - Shize Yang
- Eyring Materials Center, Arizona State University, Tempe, AZ, United States
| | - Alec Fischer
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Timothy Grotjohn
- Department of Electrical & Computer Engineering, Michigan State University, East Lansing, MI, United States
- Fraunhofer USA Center Midwest, Michigan State University, East Lansing, MI, United States
| | - Fernando Ponce
- Department of Physics, Arizona State University, Tempe, AZ, United States
| | - Peter A Crozier
- School for Engineering of Matter, Transport & Energy, Arizona State University, Tempe, AZ, United States
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29
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Zeiger PM, Barthel J, Allen LJ, Rusz J. Simulations of Phonon Spectroscopy in the Impact Scattering Regime - Advances and Applications. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:628-629. [PMID: 37613084 DOI: 10.1093/micmic/ozad067.306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Paul M Zeiger
- Uppsala University, Department of Physics and Astronomy, Uppsala, Sweden
| | - Juri Barthel
- RWTH Aachen University, Central Facility for Electron Microscopy, Aachen, Germany
- Forschungszentrum Jülich GmbH, Ernst Ruska-Centre (ER-C 2), Jülich, Germany
| | - Leslie J Allen
- University of Melbourne, School of Physics, Victoria, Australia
| | - Ján Rusz
- Uppsala University, Department of Physics and Astronomy, Uppsala, Sweden
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30
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Yan X, Gadre CA, Aoki T, Pan X. Imaging Phonon Dynamics at Hetero-Interfaces by Vibrational EELS. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:649-650. [PMID: 37613320 DOI: 10.1093/micmic/ozad067.318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Xingxu Yan
- Department of Materials Science and Engineering, University of California, Irvine, CA, USA
| | - Chaitanya A Gadre
- Department of Physics and Astronomy, University of California, Irvine, CA, USA
| | - Toshihiro Aoki
- Irvine Materials Research Institute, University of California-Irvine, Irvine, CA, USA
| | - Xiaoqing Pan
- Department of Materials Science and Engineering, University of California, Irvine, CA, USA
- Department of Physics and Astronomy, University of California, Irvine, CA, USA
- Irvine Materials Research Institute, University of California-Irvine, Irvine, CA, USA
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31
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Gadre CA, Lee T, Qi J, Ong SP, Pan X. Vibrational EELS for Solid-State Li-Ion Batteries: Mapping Li Distributions and Beyond. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:633-635. [PMID: 37613076 DOI: 10.1093/micmic/ozad067.309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Affiliation(s)
- Chaitanya A Gadre
- Department of Physics and Astronomy, University of California, Irvine, CA, USA
| | - Tom Lee
- Department of Materials Science and Engineering, University of California, Irvine, CA, USA
| | - Ji Qi
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA, USA
| | - Shyue Ping Ong
- Department of NanoEngineering, University of California San Diego, La Jolla, CA, USA
| | - Xiaoqing Pan
- Department of Physics and Astronomy, University of California, Irvine, CA, USA
- Department of Materials Science and Engineering, University of California, Irvine, CA, USA
- Irvine Materials Research Institute, University of California, Irvine, CA, USA
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32
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Hou W, Wei Y. Three-dimensional modelling of blur property for conventional optical microscopes. Heliyon 2023; 9:e17869. [PMID: 37539154 PMCID: PMC10395306 DOI: 10.1016/j.heliyon.2023.e17869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 06/25/2023] [Accepted: 06/29/2023] [Indexed: 08/05/2023] Open
Abstract
Intensity diffusion caused by optical diffraction limits the imaging resolution of conventional optical microscopes, therefore modelling and measuring the intensity transmission and distribution property of the light sources is a significant research topic in system development and pattern recognition. However, the complicated wave propagation process in optical imaging makes it difficult to provide a direct, analytical and simple mathematical model to measure the relationship between the blur degree and various camera parameters. In this study, an improved intensity transmission and distribution calculation method for conventional optical microscopes was proposed; furthermore, a simple mathematical relation between the blur degree and camera parameters was achieved based on the proposed method. First, the light intensity distribution and propagation characteristics of a conventional optical microscope were modeled based on the property of the Fresnel circular hole diffraction combined with the practical optical parameters. Second, by analyzing the property of intensity distribution and blurring imaging, a quantitative simplified mathematical relationship between the blur degree and camera parameters in optical microscope imaging was obtained, and the three-dimensional (3D) blur property in the optical imaging process was analyzed under different conditions. Third, the connection between diffractive optics and geometric optics was obtained by summarizing and generalizing the 3D blur property curve of each monochromatic light source. Finally, the proposed method was verified through a series of simulations and experiments.
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33
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Zhu Z, Yang L, Xiong Z, Liu D, Hu B, Wang N, Ola O, Zhu Y. SiC@FeZnZiF as a Bifunctional Catalyst with Catalytic Activating PMS and Photoreducing Carbon Dioxide. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13101664. [PMID: 37242081 DOI: 10.3390/nano13101664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/04/2023] [Accepted: 05/12/2023] [Indexed: 05/28/2023]
Abstract
Herein, we encapsulated modified silicon carbide nanoparticles utilizing a metal-organic backbone. E-SiC-FeZnZIF composites were successfully prepared via Fe doping. The catalysis activity of this bifunctional composite material was evaluated by the degradation of tetracycline (THC) and carbamazepine (CBZ) and the reduction of carbon dioxide (CO2). Nano SiC has received widespread attention in advanced oxidation applications, especially in the catalytic activation of peroxymonosulfate (PMS). However, the inferior activity of SiC has severely restricted its practical use. In this study of dual functional composite materials, nano SiC was firstly etched under aqueous alkali. Then, zeolite imidazolate frame-8 (ZIF-8) was used for immobilization. The filling of the etched nano SiC with FeZnZiF was confirmed by SEM, XRD, FTIR, BET, and XPS analyses. In addition, E-SiC-FeZnZIF exhibited excellent catalytic activation of peroxymonosulfate (PMS) to oxidize water pollutants, which can degrade tetracycline hydrochloride (THC), achieving a removal rate of 72% within 60 min. Moreover, E-SiC-FeZnZIF exhibited a relatively high CO2 reduction rate with H2O. The yields of CO and CH4 were 0.085 and 0.509 μmol g-1, respectively, after 2 h, which are higher than that of 50 nm of commercial SiC (CO: 0.084 μmol g-1; CH4: 0.209 μmol g-1). This work provides a relatively convenient synthesis path for constructing metal skeleton composites for advanced oxidation and photocatalytic applications. This will have practical significance in protecting water bodies and reducing CO2, which are vital not only for maintaining the natural ecological balance and negative feedback regulation, but also for creating a new application carrier based on nano silicon carbide.
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Affiliation(s)
- Zhiqi Zhu
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Liaoliao Yang
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Zhaodong Xiong
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Daohan Liu
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Binbin Hu
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Nannan Wang
- Key Laboratory of Disaster Prevention and Structural Safety of Ministry of Education, Guangxi Key Laboratory of Disaster Prevention and Engineering Safety, College of Chemistry and Chemical Engineering, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China
| | - Oluwafunmilola Ola
- Advanced Materials Group, Faculty of Engineering, The University of Nottingham, Nottingham NG7 2RD, UK
| | - Yanqiu Zhu
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF, UK
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34
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Yan X. Distinguishing atomic vibrations near point defects. NATURE MATERIALS 2023; 22:540-541. [PMID: 37138007 DOI: 10.1038/s41563-023-01538-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Affiliation(s)
- Xingxu Yan
- Department of Materials Science and Engineering, University of California, Irvine, CA, USA.
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35
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Xu M, Bao DL, Li A, Gao M, Meng D, Li A, Du S, Su G, Pennycook SJ, Pantelides ST, Zhou W. Single-atom vibrational spectroscopy with chemical-bonding sensitivity. NATURE MATERIALS 2023; 22:612-618. [PMID: 36928385 DOI: 10.1038/s41563-023-01500-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 02/06/2023] [Indexed: 05/05/2023]
Abstract
Correlation of lattice vibrational properties with local atomic configurations in materials is essential for elucidating functionalities that involve phonon transport in solids. Recent developments in vibrational spectroscopy in a scanning transmission electron microscope have enabled direct measurements of local phonon modes at defects and interfaces by combining high spatial and energy resolution. However, pushing the ultimate limit of vibrational spectroscopy in a scanning transmission electron microscope to reveal the impact of chemical bonding on local phonon modes requires extreme sensitivity of the experiment at the chemical-bond level. Here we demonstrate that, with improved instrument stability and sensitivity, the specific vibrational signals of the same substitutional impurity and the neighbouring carbon atoms in monolayer graphene with different chemical-bonding configurations are clearly resolved, complementary with density functional theory calculations. The present work opens the door to the direct observation of local phonon modes with chemical-bonding sensitivity, and provides more insights into the defect-induced physics in graphene.
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Affiliation(s)
- Mingquan Xu
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - De-Liang Bao
- Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA
| | - Aowen Li
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Meng Gao
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Dongqian Meng
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Ang Li
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Shixuan Du
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China
- Institute of Physics, Chinese Academy of Sciences, Beijing, P. R. China
| | - Gang Su
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China
- Kavli Institute for Theoretical Sciences, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Stephen J Pennycook
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China
| | - Sokrates T Pantelides
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China.
- Department of Physics and Astronomy, Vanderbilt University, Nashville, TN, USA.
- Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA.
| | - Wu Zhou
- School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences, Beijing, P. R. China.
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Lee T, Qi J, Gadre CA, Huyan H, Ko ST, Zuo Y, Du C, Li J, Aoki T, Wu R, Luo J, Ong SP, Pan X. Atomic-scale origin of the low grain-boundary resistance in perovskite solid electrolyte Li 0.375Sr 0.4375Ta 0.75Zr 0.25O 3. Nat Commun 2023; 14:1940. [PMID: 37024455 PMCID: PMC10079928 DOI: 10.1038/s41467-023-37115-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 03/02/2023] [Indexed: 04/08/2023] Open
Abstract
Oxide solid electrolytes (OSEs) have the potential to achieve improved safety and energy density for lithium-ion batteries, but their high grain-boundary (GB) resistance generally is a bottleneck. In the well-studied perovskite oxide solid electrolyte, Li3xLa2/3-xTiO3 (LLTO), the ionic conductivity of grain boundaries is about three orders of magnitude lower than that of the bulk. In contrast, the related Li0.375Sr0.4375Ta0.75Zr0.25O3 (LSTZ0.75) perovskite exhibits low grain boundary resistance for reasons yet unknown. Here, we use aberration-corrected scanning transmission electron microscopy and spectroscopy, along with an active learning moment tensor potential, to reveal the atomic scale structure and composition of LSTZ0.75 grain boundaries. Vibrational electron energy loss spectroscopy is applied for the first time to reveal atomically resolved vibrations at grain boundaries of LSTZ0.75 and to characterize the otherwise unmeasurable Li distribution therein. We find that Li depletion, which is a major reason for the low grain boundary ionic conductivity of LLTO, is absent for the grain boundaries of LSTZ0.75. Instead, the low grain boundary resistivity of LSTZ0.75 is attributed to the formation of a nanoscale defective cubic perovskite interfacial structure that contained abundant vacancies. Our study provides new insights into the atomic scale mechanisms of low grain boundary resistivity.
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Affiliation(s)
- Tom Lee
- Department of Materials Science and Engineering, University of California at Irvine, Irvine, CA, USA
| | - Ji Qi
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA, USA
| | - Chaitanya A Gadre
- Department of Physics and Astronomy, University of California at Irvine, Irvine, CA, USA
| | - Huaixun Huyan
- Department of Materials Science and Engineering, University of California at Irvine, Irvine, CA, USA
| | - Shu-Ting Ko
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA, USA
| | - Yunxing Zuo
- Department of NanoEngineering, University of California San Diego, La Jolla, CA, USA
| | - Chaojie Du
- Department of Materials Science and Engineering, University of California at Irvine, Irvine, CA, USA
| | - Jie Li
- Department of Physics and Astronomy, University of California at Irvine, Irvine, CA, USA
| | - Toshihiro Aoki
- Irvine Materials Research Institute, University of California at Irvine, Irvine, CA, USA
| | - Ruqian Wu
- Department of Physics and Astronomy, University of California at Irvine, Irvine, CA, USA.
| | - Jian Luo
- Materials Science and Engineering Program, University of California San Diego, La Jolla, CA, USA.
- Department of NanoEngineering, University of California San Diego, La Jolla, CA, USA.
| | - Shyue Ping Ong
- Department of NanoEngineering, University of California San Diego, La Jolla, CA, USA.
| | - Xiaoqing Pan
- Department of Materials Science and Engineering, University of California at Irvine, Irvine, CA, USA.
- Department of Physics and Astronomy, University of California at Irvine, Irvine, CA, USA.
- Irvine Materials Research Institute, University of California at Irvine, Irvine, CA, USA.
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37
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Chen Z, Shen X, Andrejevic N, Liu T, Luo D, Nguyen T, Drucker NC, Kozina ME, Song Q, Hua C, Chen G, Wang X, Kong J, Li M. Panoramic Mapping of Phonon Transport from Ultrafast Electron Diffraction and Scientific Machine Learning. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2206997. [PMID: 36440651 DOI: 10.1002/adma.202206997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 09/24/2022] [Indexed: 06/16/2023]
Abstract
One central challenge in understanding phonon thermal transport is a lack of experimental tools to investigate frequency-resolved phonon transport. Although recent advances in computation lead to frequency-resolved information, it is hindered by unknown defects in bulk regions and at interfaces. Here, a framework that can uncover microscopic phonon transport information in heterostructures is presented, integrating state-of-the-art ultrafast electron diffraction (UED) with advanced scientific machine learning (SciML). Taking advantage of the dual temporal and reciprocal-space resolution in UED, and the ability of SciML to solve inverse problems involving O ( 10 3 ) $\mathcal{O}({10^3})$ coupled Boltzmann transport equations, the frequency-dependent interfacial transmittance and frequency-dependent relaxation times of the heterostructure from the diffraction patterns are reliably recovered. The framework is applied to experimental Au/Si UED data, and a transport pattern beyond the diffuse mismatch model is revealed, which further enables a direct reconstruction of real-space, real-time, frequency-resolved phonon dynamics across the interface. The work provides a new pathway to probe interfacial phonon transport mechanisms with unprecedented details.
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Affiliation(s)
- Zhantao Chen
- Quantum Measurement Group, MIT, Cambridge, MA, 02139, USA
- Department of Mechanical Engineering, MIT, Cambridge, MA, 02139, USA
| | - Xiaozhe Shen
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94205, USA
| | - Nina Andrejevic
- Quantum Measurement Group, MIT, Cambridge, MA, 02139, USA
- Department of Materials Science and Engineering, MIT, Cambridge, MA, 02139, USA
| | - Tongtong Liu
- Quantum Measurement Group, MIT, Cambridge, MA, 02139, USA
- Department of Physics, MIT, Cambridge, MA, 02139, United States
| | - Duan Luo
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94205, USA
| | - Thanh Nguyen
- Quantum Measurement Group, MIT, Cambridge, MA, 02139, USA
- Department of Nuclear Science and Engineering, MIT, Cambridge, MA, 02139, USA
| | - Nathan C Drucker
- Quantum Measurement Group, MIT, Cambridge, MA, 02139, USA
- John A. Paulson School of Engineering and Applied Science, Harvard University, Cambridge, MA, 02138, USA
| | - Michael E Kozina
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94205, USA
| | - Qichen Song
- Department of Mechanical Engineering, MIT, Cambridge, MA, 02139, USA
| | - Chengyun Hua
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Gang Chen
- Department of Mechanical Engineering, MIT, Cambridge, MA, 02139, USA
| | - Xijie Wang
- SLAC National Accelerator Laboratory, Menlo Park, CA, 94205, USA
| | - Jing Kong
- Department of Electrical Engineering and Computer Science, MIT, Cambridge, MA, 02139, USA
| | - Mingda Li
- Quantum Measurement Group, MIT, Cambridge, MA, 02139, USA
- Department of Nuclear Science and Engineering, MIT, Cambridge, MA, 02139, USA
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38
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Yan X, Li J, Gu L, Gadre CA, Moore SL, Aoki T, Wang S, Zhang G, Gao Z, Basov DN, Wu R, Pan X. Curvature-Induced One-Dimensional Phonon Polaritons at Edges of Folded Boron Nitride Sheets. NANO LETTERS 2022; 22:9319-9326. [PMID: 36413202 DOI: 10.1021/acs.nanolett.2c02879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Generation and manipulation of phonon polaritons are of paramount importance for understanding the interaction between an electromagnetic field and dielectric materials and furthering their application in mid-infrared optical communication. However, the formation of tunable one-dimensional phonon polaritons has been rarely realized in van der Waals layered structures. Here we report the discovery of curvature-induced phonon polaritons localized at the crease of folded hexagonal boron nitrides (h-BNs) with a few atomic layers using monochromated electron energy-loss spectroscopy. Compared to bulk regions, the creased-localized signals undergo an abnormal blue-shift of 1.4 meV. First-principles calculations reveal that the energy shift arises from the optical phonon hardening in the curled region. Interestingly, the curvature-induced phonon polariton can also be controllably achieved via an electron-beam etching approach. This work opens an avenue of tailoring local electromagnetic response and creating unique phonon polariton modes in van der Waals layered materials for diverse applications.
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Affiliation(s)
- Xingxu Yan
- Department of Materials Science and Engineering, University of California-Irvine, Irvine, California 92697, United States
- Irvine Materials Research Institute, University of California-Irvine, Irvine, California 92697, United States
| | - Jie Li
- Department of Physics and Astronomy, University of California-Irvine, Irvine, California 92697, United States
| | - Lei Gu
- Department of Physics and Astronomy, University of California-Irvine, Irvine, California 92697, United States
| | - Chaitanya Avinash Gadre
- Department of Physics and Astronomy, University of California-Irvine, Irvine, California 92697, United States
| | - Samuel L Moore
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Toshihiro Aoki
- Irvine Materials Research Institute, University of California-Irvine, Irvine, California 92697, United States
| | - Shuopei Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100083, People's Republic of China
| | - Guangyu Zhang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100083, People's Republic of China
| | - Zhaoli Gao
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Shatin, Hong Kong 999077, People's Republic of China
| | - Dimitri N Basov
- Department of Physics, Columbia University, New York, New York 10027, United States
| | - Ruqian Wu
- Department of Physics and Astronomy, University of California-Irvine, Irvine, California 92697, United States
| | - Xiaoqing Pan
- Department of Materials Science and Engineering, University of California-Irvine, Irvine, California 92697, United States
- Department of Physics and Astronomy, University of California-Irvine, Irvine, California 92697, United States
- Irvine Materials Research Institute, University of California-Irvine, Irvine, California 92697, United States
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39
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Konečná A, Iyikanat F, García de Abajo FJ. Entangling free electrons and optical excitations. SCIENCE ADVANCES 2022; 8:eabo7853. [PMID: 36427323 PMCID: PMC9699672 DOI: 10.1126/sciadv.abo7853] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 10/07/2022] [Indexed: 05/30/2023]
Abstract
The inelastic interaction between flying particles and optical nanocavities gives rise to entangled states in which some excitations of the latter are paired with momentum changes in the former. Specifically, free-electron entanglement with nanocavity modes opens appealing opportunities associated with the strong interaction capabilities of the electrons. However, the achievable degree of entanglement is currently limited by the lack of control over the resulting state mixtures. Here, we propose a scheme to generate pure entanglement between designated optical-cavity excitations and separable free-electron states. We shape the electron wave function profile to select the accessible cavity modes and simultaneously associate them with targeted electron scattering directions. This concept is exemplified through theoretical calculations of free-electron entanglement with degenerate and nondegenerate plasmon modes in silver nanoparticles and atomic vibrations in an inorganic molecule. The generated entanglement can be further propagated through its electron component to extend quantum interactions beyond existing protocols.
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Affiliation(s)
- Andrea Konečná
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona 08860, Spain
- Central European Institute of Technology, Brno University of Technology, Brno 61200, Czech Republic
| | - Fadil Iyikanat
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona 08860, Spain
| | - F. Javier García de Abajo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona 08860, Spain
- ICREA-Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys 23, 08010 Barcelona, Spain
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40
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Yang H, Konečná A, Xu X, Cheong SW, Batson PE, García de Abajo FJ, Garfunkel E. Simultaneous Imaging of Dopants and Free Charge Carriers by Monochromated EELS. ACS NANO 2022; 16:18795-18805. [PMID: 36317944 DOI: 10.1021/acsnano.2c07540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Doping inhomogeneities in solids are not uncommon, but their microscopic observation and understanding are limited due to the lack of bulk-sensitive experimental techniques with high enough spatial and spectral resolution. Here, we demonstrate nanoscale imaging of both dopants and free charge carriers in La-doped BaSnO3 (BLSO) using high-resolution electron energy-loss spectroscopy (EELS). By analyzing high- and low-energy excitations in EELS, we reveal chemical and electronic inhomogeneities within a single BLSO nanocrystal. The inhomogeneous doping leads to distinctive localized infrared surface plasmons, including a previously unobserved plasmon mode that is highly confined between high- and low-doping regions. We further quantify the carrier density, effective mass, and dopant activation percentage by EELS and transport measurements on the bulk single crystals of BLSO. These results not only represent a practical approach for studying heterogeneities in solids and understanding structure-property relationships at the nanoscale, but also demonstrate the possibility of infrared plasmon tuning by leveraging nanoscale doping texture.
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Affiliation(s)
- Hongbin Yang
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey08854, United States
| | - Andrea Konečná
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860Castelldefels, Barcelona, Spain
- Central European Institute of Technology, Brno University of Technology, 61200Brno, Czech Republic
| | - Xianghan Xu
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey08854, United States
| | - Sang-Wook Cheong
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey08854, United States
| | - Philip E Batson
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey08854, United States
| | - F Javier García de Abajo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860Castelldefels, Barcelona, Spain
- ICREA-Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys 23, 08010Barcelona, Spain
| | - Eric Garfunkel
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey08854, United States
- Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey08854, United States
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41
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Song X, Zhang X, Chang Q, Yao X, Li M, Zhang R, Liu X, Song C, Ng YXA, Ang EH, Ou Z. High-Resolution Electron Tomography of Ultrathin Boerdijk-Coxeter-Bernal Nanowire Enabled by Superthin Metal Surface Coating. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2203310. [PMID: 36084232 DOI: 10.1002/smll.202203310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 08/22/2022] [Indexed: 06/15/2023]
Abstract
The rapid advancement of transmission electron microscopy has resulted in revolutions in a variety of fields, including physics, chemistry, and materials science. With single-atom resolution, 3D information of each atom in nanoparticles is revealed, while 4D electron tomography is shown to capture the atomic structural kinetics in metal nanoparticles after phase transformation. Quantitative measurements of physical and chemical properties such as chemical coordination, defects, dislocation, and local strain have been made. However, due to the incompatibility of high dose rate with other ultrathin morphologies, such as nanowires, atomic electron tomography has been primarily limited to quasi-spherical nanoparticles. Herein, the 3D atomic structure of a complex core-shell nanowire composed of an ultrathin Boerdijk-Coxeter-Bernal (BCB) core nanowire and a noble metal thin layer shell deposited on the BCB nanowire surface is discovered. Furthermore, it is demonstrated that a new superthin noble metal layer deposition on an ultrathin BCB nanowire could mitigate electron beam damage using an in situ transmission electron microscope and atomic resolution electron tomography. The colloidal coating method developed for electron tomography can be broadly applied to protect the ultrathin nanomaterials from electron beam damage, benefiting both the advanced material characterizations and enabling fundamental in situ mechanistic studies.
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Affiliation(s)
- Xiaohui Song
- School of Materials Science and Engineering, Hefei University of Technology, Hefei, Anhui Province, 230009, China
- Department of Materials Science and Engineering, University of California at Berkeley & The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Xingyu Zhang
- Faculty of Materials and Manufacting, Beijing University of Technology, Pingleyuan 100, Beijng, 100124, China
| | - Qiang Chang
- School of Materials Science and Engineering, Hefei University of Technology, Hefei, Anhui Province, 230009, China
| | - Xin Yao
- School of Materials Science and Engineering, Hefei University of Technology, Hefei, Anhui Province, 230009, China
| | - Mufan Li
- Chemistry Department, University of California at Berkeley & Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Ruopeng Zhang
- Department of Materials Science and Engineering, University of California at Berkeley & The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Xiaotao Liu
- Department of Materials Science and Engineering, University of California at Berkeley & The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Chengyu Song
- Department of Materials Science and Engineering, University of California at Berkeley & The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Yun Xin Angel Ng
- Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, Singapore, 637616, Singapore
| | - Edison Huixiang Ang
- Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, Singapore, 637616, Singapore
| | - Zihao Ou
- School of Materials Science and Engineering, Stanford University, Stanford, CA, 94305, USA
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42
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Zhao H, Zhu Y, Ye H, He Y, Li H, Sun Y, Yang F, Wang R. Atomic-Scale Structure Dynamics of Nanocrystals Revealed By In Situ and Environmental Transmission Electron Microscopy. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022:e2206911. [PMID: 36153832 DOI: 10.1002/adma.202206911] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 09/05/2022] [Indexed: 06/16/2023]
Abstract
Nanocrystals are of great importance in material sciences and industry. Engineering nanocrystals with desired structures and properties is no doubt one of the most important challenges in the field, which requires deep insight into atomic-scale dynamics of nanocrystals during the process. The rapid developments of in situ transmission electron microscopy (TEM), especially environmental TEM, reveal insights into nanocrystals to digest. According to the considerable progress based on in situ electron microscopy, a comprehensive review on nanocrystal dynamics from three aspects: nucleation and growth, structure evolution, and dynamics in reaction conditions are given. In the nucleation and growth part, existing nucleation theories and growth pathways are organized based on liquid and gas-solid phases. In the structure evolution part, the focus is on in-depth mechanistic understanding of the evolution, including defects, phase, and disorder/order transitions. In the part of dynamics in reaction conditions, solid-solid and gas-solid interfaces of nanocrystals in atmosphere are discussed and the structure-property relationship is correlated. Even though impressive progress is made, additional efforts are required to develop the integrated and operando TEM methodologies for unveiling nanocrystal dynamics with high spatial, energy, and temporal resolutions.
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Affiliation(s)
- Haofei Zhao
- Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yuchen Zhu
- Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Huanyu Ye
- Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yang He
- Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Hao Li
- Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yifei Sun
- Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
| | - Feng Yang
- Department of Chemistry, Guangdong Provincial Key Laboratory of Catalysis, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Rongming Wang
- Beijing Advanced Innovation Center for Materials Genome Engineering, University of Science and Technology Beijing, Beijing, 100083, China
- Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing, Beijing, 100083, China
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43
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García de Abajo FJ, Dias EJC, Di Giulio V. Complete Excitation of Discrete Quantum Systems by Single Free Electrons. PHYSICAL REVIEW LETTERS 2022; 129:093401. [PMID: 36083663 DOI: 10.1103/physrevlett.129.093401] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 07/26/2022] [Indexed: 06/15/2023]
Abstract
We reveal a wealth of nonlinear and recoil effects in the interaction between individual low-energy electrons (≲100 eV) and samples comprising a discrete number of states. Adopting a quantum theoretical description of combined free-electron and two-level systems, we find a maximum achievable excitation probability of 100%, which requires specific conditions relating to the coupling strength and the transition symmetry, as we illustrate through calculations for dipolar and quadrupolar modes. Strong recoil effects are observed when the kinetic energy of the probe lies close to the transition threshold, although the associated probability remains independent of the electron wave function even when fully accounting for nonlinear interactions with arbitrarily complex multilevel samples. Our work reveals the potential of free electrons to control localized excitations and delineates the boundaries of such control.
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Affiliation(s)
- F Javier García de Abajo
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
- ICREA-Institució Catalana de Recerca i Estudis Avançats, Passeig Lluís Companys 23, 08010 Barcelona, Spain
| | - Eduardo J C Dias
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
| | - Valerio Di Giulio
- ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
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44
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Gadre CA, Yan X, Song Q, Li J, Gu L, Huyan H, Aoki T, Lee SW, Chen G, Wu R, Pan X. Nanoscale imaging of phonon dynamics by electron microscopy. Nature 2022; 606:292-297. [PMID: 35676428 PMCID: PMC9177420 DOI: 10.1038/s41586-022-04736-8] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 04/07/2022] [Indexed: 11/08/2022]
Abstract
Spatially resolved vibrational mapping of nanostructures is indispensable to the development and understanding of thermal nanodevices1, modulation of thermal transport2 and novel nanostructured thermoelectric materials3-5. Through the engineering of complex structures, such as alloys, nanostructures and superlattice interfaces, one can significantly alter the propagation of phonons and suppress material thermal conductivity while maintaining electrical conductivity2. There have been no correlative experiments that spatially track the modulation of phonon properties in and around nanostructures due to spatial resolution limitations of conventional optical phonon detection techniques. Here we demonstrate two-dimensional spatial mapping of phonons in a single silicon-germanium (SiGe) quantum dot (QD) using monochromated electron energy loss spectroscopy in the transmission electron microscope. Tracking the variation of the Si optical mode in and around the QD, we observe the nanoscale modification of the composition-induced red shift. We observe non-equilibrium phonons that only exist near the interface and, furthermore, develop a novel technique to differentially map phonon momenta, providing direct evidence that the interplay between diffuse and specular reflection largely depends on the detailed atomistic structure: a major advancement in the field. Our work unveils the non-equilibrium phonon dynamics at nanoscale interfaces and can be used to study actual nanodevices and aid in the understanding of heat dissipation near nanoscale hotspots, which is crucial for future high-performance nanoelectronics.
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Affiliation(s)
- Chaitanya A Gadre
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Xingxu Yan
- Department of Materials Science and Engineering, University of California Irvine, Irvine, CA, USA
- Irvine Materials Research Institute, University of California Irvine, Irvine, CA, USA
| | - Qichen Song
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Jie Li
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Lei Gu
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Huaixun Huyan
- Department of Materials Science and Engineering, University of California Irvine, Irvine, CA, USA
| | - Toshihiro Aoki
- Irvine Materials Research Institute, University of California Irvine, Irvine, CA, USA
| | - Sheng-Wei Lee
- Institute of Materials Science and Engineering, National Central University, Taoyuan, Taiwan
| | - Gang Chen
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Ruqian Wu
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA
| | - Xiaoqing Pan
- Department of Physics and Astronomy, University of California Irvine, Irvine, CA, USA.
- Department of Materials Science and Engineering, University of California Irvine, Irvine, CA, USA.
- Irvine Materials Research Institute, University of California Irvine, Irvine, CA, USA.
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Nanoscale map shows how interfaces impede vibrations. Nature 2022; 606:252-253. [PMID: 35676426 DOI: 10.1038/d41586-022-01533-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Rez P, Boland T, Elsässer C, Singh A. Localized Phonon Densities of States at Grain Boundaries in Silicon. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2022; 28:1-8. [PMID: 35293309 DOI: 10.1017/s143192762200040x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Since it is now possible to record vibrational spectra at nanometer scales in the electron microscope, it is of interest to explore whether extended defects in crystals such as dislocations or grain boundaries will result in measurable changes of the phonon densities of states (dos) that are reflected in the spectra. Phonon densities of states were calculated for a set of high angle grain boundaries in silicon. The boundaries are modeled by supercells with up to 160 atoms, and the vibrational densities of states were calculated by taking the Fourier transform of the velocity–velocity autocorrelation function from molecular dynamics simulations with larger supercells doubled in all three directions. In selected cases, the results were checked on the original supercells by comparison with the densities of states obtained by diagonalizing the dynamical matrix calculated using density functional theory. Near the core of the grain boundary, the height of the optic phonon peak in the dos at 60 meV was suppressed relative to features due to acoustic phonons that are largely unchanged relative to their bulk values. This can be attributed to the variation in the strength of bonds in grain boundary core regions where there is a range of bond lengths.
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Affiliation(s)
- Peter Rez
- Department of Physics, Arizona State University, Tempe, AZ85287-1504, USA
| | - Tara Boland
- School For Engineering of Matter Transport and Energy, Arizona State University, Tempe, AZ85287-6106, USA
| | - Christian Elsässer
- Fraunhofer Institute for Mechanics of Materials IWM, Wöhlerstraße 11, 79108Freiburg, Germany
| | - Arunima Singh
- Department of Physics, Arizona State University, Tempe, AZ85287-1504, USA
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Hachtel JA. Isotopes tracked on a sub-nanometre scale using electron spectroscopy. Nature 2022; 603:36-37. [PMID: 35236970 DOI: 10.1038/d41586-022-00545-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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48
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Senga R, Lin YC, Morishita S, Kato R, Yamada T, Hasegawa M, Suenaga K. Imaging of isotope diffusion using atomic-scale vibrational spectroscopy. Nature 2022; 603:68-72. [PMID: 35236976 DOI: 10.1038/s41586-022-04405-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 01/05/2022] [Indexed: 11/09/2022]
Abstract
The spatial resolutions of even the most sensitive isotope analysis techniques based on light or ion probes are limited to a few hundred nanometres. Although vibrational spectroscopy using electron probes has achieved higher spatial resolution1-3, the detection of isotopes at the atomic level4 has been challenging so far. Here we show the unambiguous isotopic imaging of 12C carbon atoms embedded in 13C graphene and the monitoring of their self-diffusion via atomic-level vibrational spectroscopy. We first grow a domain of 12C carbon atoms in a pre-existing crack of 13C graphene, which is then annealed at 600 degrees Celsius for several hours. Using scanning transmission electron microscopy-electron energy loss spectroscopy, we obtain an isotope map that confirms the segregation of 12C atoms that diffused rapidly. The map also indicates that the graphene layer becomes isotopically homogeneous over 100-nanometre regions after 2 hours. Our results demonstrate the high mobility of carbon atoms during growth and annealing via self-diffusion. This imaging technique can provide a fundamental methodology for nanoisotope engineering and monitoring, which will aid in the creation of isotope labels and tracing at the nanoscale.
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Affiliation(s)
- Ryosuke Senga
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan.
| | - Yung-Chang Lin
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan
| | | | - Ryuichi Kato
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan
| | - Takatoshi Yamada
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan
| | - Masataka Hasegawa
- Nanomaterials Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ibaraki, Japan
| | - Kazu Suenaga
- The Institute of Scientific and Industrial Research (ISIR), Osaka University, Ibaraki, Japan.
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Atomic-scale probing of heterointerface phonon bridges in nitride semiconductor. Proc Natl Acad Sci U S A 2022; 119:2117027119. [PMID: 35181607 PMCID: PMC8872775 DOI: 10.1073/pnas.2117027119] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/17/2022] [Indexed: 11/18/2022] Open
Abstract
Interface phonon modes that are generated by several atomic layers at the heterointerface play a major role in the interface thermal conductance for nanoscale high-power devices such as nitride-based high-electron-mobility transistors and light-emitting diodes. Here we measure the local phonon spectra across AlN/Si and AlN/Al interfaces using atomically resolved vibrational electron energy-loss spectroscopy in a scanning transmission electron microscope. At the AlN/Si interface, we observe various interface phonon modes, of which the extended and localized modes act as bridges to connect the bulk AlN modes and bulk Si modes and are expected to boost the phonon transport, thus substantially contributing to interface thermal conductance. In comparison, no such phonon bridge is observed at the AlN/Al interface, for which partially extended modes dominate the interface thermal conductivity. This work provides valuable insights into understanding the interfacial thermal transport in nitride semiconductors and useful guidance for thermal management via interface engineering.
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Ko W, Gai Z, Puretzky AA, Liang L, Berlijn T, Hachtel JA, Xiao K, Ganesh P, Yoon M, Li AP. Understanding Heterogeneities in Quantum Materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022:e2106909. [PMID: 35170112 DOI: 10.1002/adma.202106909] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 02/08/2022] [Indexed: 06/14/2023]
Abstract
Quantum materials are usually heterogeneous, with structural defects, impurities, surfaces, edges, interfaces, and disorder. These heterogeneities are sometimes viewed as liabilities within conventional systems; however, their electronic and magnetic structures often define and affect the quantum phenomena such as coherence, interaction, entanglement, and topological effects in the host system. Therefore, a critical need is to understand the roles of heterogeneities in order to endow materials with new quantum functions for energy and quantum information science applications. In this article, several representative examples are reviewed on the recent progress in connecting the heterogeneities to the quantum behaviors of real materials. Specifically, three intertwined topic areas are assessed: i) Reveal the structural, electronic, magnetic, vibrational, and optical degrees of freedom of heterogeneities. ii) Understand the effect of heterogeneities on the behaviors of quantum states in host material systems. iii) Control heterogeneities for new quantum functions. This progress is achieved by establishing the atomistic-level structure-property relationships associated with heterogeneities in quantum materials. The understanding of the interactions between electronic, magnetic, photonic, and vibrational states of heterogeneities enables the design of new quantum materials, including topological matter and quantum light emitters based on heterogenous 2D materials.
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Affiliation(s)
- Wonhee Ko
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Zheng Gai
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Alexander A Puretzky
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Liangbo Liang
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Tom Berlijn
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Jordan A Hachtel
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Kai Xiao
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Panchapakesan Ganesh
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - Mina Yoon
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
| | - An-Ping Li
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee, 37831, USA
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