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Muraleedharan AK, Co K, Vallet M, Zaki A, Karolak F, Bogicevic C, Perronet K, Dkhil B, Paillard C, Fiorini-Debuisschert C, Treussart F. Ferroelectric Texture of Individual Barium Titanate Nanocrystals. ACS NANO 2024; 18:18355-18367. [PMID: 38952163 DOI: 10.1021/acsnano.4c02291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Abstract
Ferroelectric materials display exotic polarization textures at the nanoscale that could be used to improve the energetic efficiency of electronic components. The vast majority of studies were conducted in two dimensions on thin films that can be further nanostructured, but very few studies address the situation of individual isolated nanocrystals (NCs) synthesized in solution, while such structures could have other fields of applications. In this work, we experimentally and theoretically studied the polarization texture of ferroelectric barium titanate (BaTiO3, BTO) NCs attached to a conductive substrate and surrounded by air. We synthesized NCs of well-defined quasicubic shape and 160 nm average size that conserve the tetragonal structure of BTO at room temperature. We then investigated the inverse piezoelectric properties of such pristine individual NCs by vector piezoresponse force microscopy (PFM), taking particular care to suppress electrostatic artifacts. In all of the NCs studied, we could not detect any vertical PFM signal, and the maps of the lateral response all displayed larger displacement amplitude on the edges with deformations converging toward the center. Using field phase simulations dedicated to ferroelectric nanostructures, we were able to predict the equilibrium polarization texture. These simulations revealed that the NC core is composed of 180° up and down domains defining the polar axis that rotate by 90° in the two facets orthogonal to this axis, eventually lying within these planes forming a layer of about 10 nm thickness mainly composed of 180° domains along an edge. From this polarization distribution, we predicted the lateral PFM response, which was revealed to be in very good qualitative agreement with the experimental observations. This work positions PFM as a relevant tool to evaluate the potential of complex ferroelectric nanostructures to be used as sensors.
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Affiliation(s)
- Athulya K Muraleedharan
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, CentraleSupélec, LuMIn, 91190 Gif-sur-Yvette, France
| | - Kevin Co
- Université Paris-Saclay, CentraleSupélec, CNRS, Laboratoire SPMS, 91190 Gif-sur-Yvette, France
| | - Maxime Vallet
- Université Paris-Saclay, CentraleSupélec, CNRS, Laboratoire SPMS, 91190 Gif-sur-Yvette, France
| | - Abdelali Zaki
- Université Paris-Saclay, CentraleSupélec, CNRS, Laboratoire SPMS, 91190 Gif-sur-Yvette, France
| | - Fabienne Karolak
- Université Paris-Saclay, CentraleSupélec, CNRS, Laboratoire SPMS, 91190 Gif-sur-Yvette, France
| | - Christine Bogicevic
- Université Paris-Saclay, CentraleSupélec, CNRS, Laboratoire SPMS, 91190 Gif-sur-Yvette, France
| | - Karen Perronet
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, CentraleSupélec, LuMIn, 91190 Gif-sur-Yvette, France
| | - Brahim Dkhil
- Université Paris-Saclay, CentraleSupélec, CNRS, Laboratoire SPMS, 91190 Gif-sur-Yvette, France
| | - Charles Paillard
- Université Paris-Saclay, CentraleSupélec, CNRS, Laboratoire SPMS, 91190 Gif-sur-Yvette, France
- Smart Ferroic Materials Center, Institute for Nanoscience & Engineering and Department of Physics, University of Arkansas, Fayetteville, 72701 Arkansas, United States
| | | | - François Treussart
- Université Paris-Saclay, ENS Paris-Saclay, CNRS, CentraleSupélec, LuMIn, 91190 Gif-sur-Yvette, France
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2
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Zhu R, Zheng S, Li X, Wang T, Tan C, Yu T, Liu Z, Wang X, Li J, Wang J, Gao P. Atomic-Scale Tracking Topological Phase Transition Dynamics of Polar Vortex-Antivortex Pairs. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2312072. [PMID: 38734889 DOI: 10.1002/adma.202312072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 04/02/2024] [Indexed: 05/13/2024]
Abstract
Non-trivial topological structures, such as vortex-antivortex (V-AV) pairs, have garnered significant attention in the field of condensed matter physics. However, the detailed topological phase transition dynamics of V-AV pairs, encompassing behaviors like self-annihilation, motion, and dissociation, have remained elusive in real space. Here, polar V-AV pairs are employed as a model system, and their transition pathways are tracked with atomic-scale resolution, facilitated by in situ (scanning) transmission electron microscopy and phase field simulations. This investigation reveals that polar vortices and antivortices can stably coexist as bound pairs at room temperature, and their polarization decreases with heating. No dissociation behavior is observed between the V-AV phase at room temperature and the paraelectric phase at high temperature. However, the application of electric fields can promote the approach of vortex and antivortex cores, ultimately leading to their annihilation near the interface. Revealing the transition process mediated by polar V-AV pairs at the atomic scale, particularly the role of polar antivortex, provides new insights into understanding the topological phases of matter and their topological phase transitions. Moreover, the detailed exploration of the dynamics of polar V-AV pairs under thermal and electrical fields lays a solid foundation for their potential applications in electronic devices.
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Affiliation(s)
- Ruixue Zhu
- Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
| | - Sizheng Zheng
- Department of Engineering Mechanics, Zhejiang University, Hangzhou, Zhejiang, 310027, China
| | - Xiaomei Li
- Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
- School of Integrated Circuits, East China Normal University, Shanghai, 200241, China
| | - Tao Wang
- Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
| | - Congbing Tan
- Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials, School of Physics and Electronics, Hunan University of Science and Technology, Xiangtan, Hunan, 411201, China
| | - Tiancheng Yu
- Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
| | - Zhetong Liu
- Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
| | - Xinqiang Wang
- State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing, 100871, China
- Collaborative Innovation Centre of Quantum Matter, Beijing, 100871, China
| | - Jiangyu Li
- Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, 518055, China
| | - Jie Wang
- Department of Engineering Mechanics, Zhejiang University, Hangzhou, Zhejiang, 310027, China
- Zhejiang Laboratory, Hangzhou, 311100, China
| | - Peng Gao
- Electron Microscopy Laboratory, and International Center for Quantum Materials, School of Physics, Peking University, Beijing, 100871, China
- Collaborative Innovation Centre of Quantum Matter, Beijing, 100871, China
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3
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Wang Z, Chen LQ. Tuning Topology Phases by Controlling Effective Screening and Depolarization in Oxide Superlattices. NANO LETTERS 2024; 24:5761-5766. [PMID: 38709952 DOI: 10.1021/acs.nanolett.4c00858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Polar topological phases in oxide superlattices attracted significant attention due to their unique properties. Previous work revealed that a polar vortex and polar skyrmions exist in (PTO)/(STO) superlattices under different elastic constraints, i.e., on different substrates. Here, our phase-field simulation demonstrates that manipulating the PTO and STO layers' thickness can control the effective screening provided by STO and the depolarization degree in PTO, thus switching the system among the polar skyrmions, vortex labyrinth, or paraelectric phase without changing elastic constraints. Additionally, reducing the STO thickness creates interlayer coupling among PTO layers, generating the long-range order of topological phases within superlattices. Furthermore, we construct a PTO-STO thickness topological phase diagram. These findings offer insights into the polar topological phases' formation in oxide superlattices, elucidating the roles of ferroelectric and paraelectric layers in their formation.
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Affiliation(s)
- Zhiyang Wang
- Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Long-Qing Chen
- Department of Materials Science and Engineering, Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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4
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Jeong C, Lee J, Jo H, Oh J, Baik H, Go KJ, Son J, Choi SY, Prosandeev S, Bellaiche L, Yang Y. Revealing the three-dimensional arrangement of polar topology in nanoparticles. Nat Commun 2024; 15:3887. [PMID: 38719801 PMCID: PMC11078976 DOI: 10.1038/s41467-024-48082-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 04/16/2024] [Indexed: 05/12/2024] Open
Abstract
In the early 2000s, low dimensional ferroelectric systems were predicted to have topologically nontrivial polar structures, such as vortices or skyrmions, depending on mechanical or electrical boundary conditions. A few variants of these structures have been experimentally observed in thin film model systems, where they are engineered by balancing electrostatic charge and elastic distortion energies. However, the measurement and classification of topological textures for general ferroelectric nanostructures have remained elusive, as it requires mapping the local polarization at the atomic scale in three dimensions. Here we unveil topological polar structures in ferroelectric BaTiO3 nanoparticles via atomic electron tomography, which enables us to reconstruct the full three-dimensional arrangement of cation atoms at an individual atom level. Our three-dimensional polarization maps reveal clear topological orderings, along with evidence of size-dependent topological transitions from a single vortex structure to multiple vortices, consistent with theoretical predictions. The discovery of the predicted topological polar ordering in nanoscale ferroelectrics, independent of epitaxial strain, widens the research perspective and offers potential for practical applications utilizing contact-free switchable toroidal moments.
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Affiliation(s)
- Chaehwa Jeong
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Juhyeok Lee
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
- Energy Geosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Hyesung Jo
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Jaewhan Oh
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea
| | - Hionsuck Baik
- Korea Basic Science Institute (KBSI), Seoul, 02841, Republic of Korea
| | - Kyoung-June Go
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
| | - Junwoo Son
- Department of Materials Science and Engineering, Research Institute of Advanced Materials, Seoul National University, Seoul, 08826, Republic of Korea
| | - Si-Young Choi
- Department of Materials Science and Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, Republic of Korea
- Center for Van der Waals Quantum Solids, Institute for Basic Science (IBS), Pohang, 37673, Republic of Korea
| | - Sergey Prosandeev
- Smart Ferroic Materials Center (SFMC), Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Laurent Bellaiche
- Smart Ferroic Materials Center (SFMC), Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, 72701, USA
| | - Yongsoo Yang
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
- Graduate School of Semiconductor Technology, School of Electrical Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
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5
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Wang JH, Zhu MX, Li YS, Chen SJ, Gong FH, Lv XD, Jiang RJ, Liu SZ, Li C, Wang YJ, Tang YL, Zhu YL, Ma XL. Large Polarization Near 50 μC/cm 2 in a Single Unit Cell Layer SrTiO 3. NANO LETTERS 2024; 24:4082-4090. [PMID: 38526914 DOI: 10.1021/acs.nanolett.3c04695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
The generally nonpolar SrTiO3 has attracted more attention recently because of its possibly induced novel polar states and related paraelectric-ferroelectric phase transitions. By using controlled pulsed laser deposition, high-quality, ultrathin, and strained SrTiO3 layers were obtained. Here, transmission electron microscopy and theoretical simulations have unveiled highly polar states in SrTiO3 films even down to one unit cell at room temperature, which were stabilized in the PbTiO3/SrTiO3/PbTiO3 sandwich structures by in-plane tensile strain and interfacial coupling, as evidenced by large tetragonality (∼1.05), notable polar ion displacement (0.019 nm), and thus ultrahigh spontaneous polarization (up to ∼50 μC/cm2). These values are nearly comparable to those of the strong ferroelectrics as the PbZrxTi1-xO3 family. Our findings provide an effective and practical approach for integrating large strain states into oxide films and inducing polarization in nonpolar materials, which may broaden the functionality of nonpolar oxides and pave the way for the discovery of new electronic materials.
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Affiliation(s)
- Jing-Hui Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Mei-Xiong Zhu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Yu-Shu Li
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Shuang-Jie Chen
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Feng-Hui Gong
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan 523808, China
| | - Xiao-Dong Lv
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Ru-Jian Jiang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Su-Zhen Liu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Changji Li
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Yu-Jia Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
| | - Yun-Long Tang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Shenyang 110016, China
| | - Yin-Lian Zhu
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan 523808, China
- School of Materials Science and Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
| | - Xiu-Liang Ma
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan 523808, China
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
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6
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Meisenheimer P, Ghosal A, Hoglund E, Wang Z, Behera P, Gómez-Ortiz F, Kavle P, Karapetrova E, García-Fernández P, Martin LW, Raja A, Chen LQ, Hopkins PE, Junquera J, Ramesh R. Interlayer Coupling Controlled Ordering and Phases in Polar Vortex Superlattices. NANO LETTERS 2024; 24:2972-2979. [PMID: 38416567 PMCID: PMC10941248 DOI: 10.1021/acs.nanolett.3c03738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 03/01/2024]
Abstract
The recent discovery of polar topological structures has opened the door for exciting physics and emergent properties. There is, however, little methodology to engineer stability and ordering in these systems, properties of interest for engineering emergent functionalities. Notably, when the surface area is extended to arbitrary thicknesses, the topological polar texture becomes unstable. Here we show that this instability of the phase is due to electrical coupling between successive layers. We demonstrate that this electrical coupling is indicative of an effective screening length in the dielectric, similar to the conductor-ferroelectric interface. Controlling the electrostatics of the superlattice interfaces, the system can be tuned between a pure topological vortex state and a mixed classical-topological phase. This coupling also enables engineering coherency among the vortices, not only tuning the bulk phase diagram but also enabling the emergence of a 3D lattice of polar textures.
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Affiliation(s)
- Peter Meisenheimer
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
| | - Arundhati Ghosal
- Department
of Physics, University of California, Berkeley, California 94720, United States
| | - Eric Hoglund
- Center
for Nanophase Materials Sciences, Oak Ridge
National Laboratory, Oak Ridge, Tennessee 37830, United States
- Department
of Materials Science and Engineering, Department of Mechanical and Aerospace
Engineering, Department of Physics, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Zhiyang Wang
- Department
of Materials Science and Engineering, Penn
State University, State
College, Pennsylvania 16801, United States
| | - Piush Behera
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
| | - Fernando Gómez-Ortiz
- Departamento
de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Avenida de los Castros s/n, 39005 Santander, Spain
| | - Pravin Kavle
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
| | - Evguenia Karapetrova
- Advanced
Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Pablo García-Fernández
- Departamento
de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Avenida de los Castros s/n, 39005 Santander, Spain
| | - Lane W. Martin
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Department
of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, United States
| | - Archana Raja
- Molecular
Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Long-Qing Chen
- Department
of Materials Science and Engineering, Penn
State University, State
College, Pennsylvania 16801, United States
| | - Patrick E. Hopkins
- Department
of Materials Science and Engineering, Department of Mechanical and Aerospace
Engineering, Department of Physics, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Javier Junquera
- Departamento
de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Avenida de los Castros s/n, 39005 Santander, Spain
| | - Ramamoorthy Ramesh
- Department
of Materials Science and Engineering, University
of California, Berkeley, California 94720, United States
- Department
of Physics, University of California, Berkeley, California 94720, United States
- Materials
Sciences Division, Lawrence Berkeley National
Laboratory, Berkeley, California 94720, United States
- Department
of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, United States
- Department
of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
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7
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Guo M, Xu E, Huang H, Guo C, Chen H, Chen S, He S, Zhou L, Ma J, Shen Z, Xu B, Yi D, Gao P, Nan CW, Mathur ND, Shen Y. Electrically and mechanically driven rotation of polar spirals in a relaxor ferroelectric polymer. Nat Commun 2024; 15:348. [PMID: 38191601 PMCID: PMC10774403 DOI: 10.1038/s41467-023-44395-5] [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: 09/07/2023] [Accepted: 12/12/2023] [Indexed: 01/10/2024] Open
Abstract
Topology created by quasi-continuous spatial variations of a local polarization direction represents an exotic state of matter, but field-driven manipulation has been hitherto limited to creation and destruction. Here we report that relatively small electric or mechanical fields can drive the non-volatile rotation of polar spirals in discretized microregions of the relaxor ferroelectric polymer poly(vinylidene fluoride-ran-trifluoroethylene). These polar spirals arise from the asymmetric Coulomb interaction between vertically aligned helical polymer chains, and can be rotated in-plane through various angles with robust retention. Given also that our manipulation of topological order can be detected via infrared absorption, our work suggests a new direction for the application of complex materials.
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Affiliation(s)
- Mengfan Guo
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China.
- Department of Materials Science, University of Cambridge, 27 Charles Babbage Road, CB3 0FS, Cambridge, UK.
| | - Erxiang Xu
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Houbing Huang
- School of Materials Science and Engineering & Advanced Research Institute of Multidisciplinary Science; Beijing Institute of Technology, 100081, Beijing, China
| | - Changqing Guo
- School of Materials Science and Engineering & Advanced Research Institute of Multidisciplinary Science; Beijing Institute of Technology, 100081, Beijing, China
| | - Hetian Chen
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Shulin Chen
- Changsha Semiconductor Technology and Application Innovation Research Institute, College of Semiconductors (College of Integrated Circuits), Hunan University, 410082, Changsha, China
| | - Shan He
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Le Zhou
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Jing Ma
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Zhonghui Shen
- International School of Materials Science and Engineering, Wuhan University of Technology, 430070, Wuhan, China
| | - Ben Xu
- Department of Graduate School, China Academy of Engineering Physics, 100193, Beijing, China
| | - Di Yi
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Peng Gao
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, 100871, Beijing, China
| | - Ce-Wen Nan
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Neil D Mathur
- Department of Materials Science, University of Cambridge, 27 Charles Babbage Road, CB3 0FS, Cambridge, UK.
| | - Yang Shen
- State Key Lab of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China.
- Center for Flexible Electronics Technology, Tsinghua University, 100084, Beijing, China.
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8
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Susarla S, Hsu S, Gómez-Ortiz F, García-Fernández P, Savitzky BH, Das S, Behera P, Junquera J, Ercius P, Ramesh R, Ophus C. The emergence of three-dimensional chiral domain walls in polar vortices. Nat Commun 2023; 14:4465. [PMID: 37491370 PMCID: PMC10368707 DOI: 10.1038/s41467-023-40009-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 07/07/2023] [Indexed: 07/27/2023] Open
Abstract
Chirality or handedness of a material can be used as an order parameter to uncover the emergent electronic properties for quantum information science. Conventionally, chirality is found in naturally occurring biomolecules and magnetic materials. Chirality can be engineered in a topological polar vortex ferroelectric/dielectric system via atomic-scale symmetry-breaking operations. We use four-dimensional scanning transmission electron microscopy (4D-STEM) to map out the topology-driven three-dimensional domain walls, where the handedness of two neighbor topological domains change or remain the same. The nature of the domain walls is governed by the interplay of the local perpendicular (lateral) and parallel (axial) polarization with respect to the tubular vortex structures. Unique symmetry-breaking operations and the finite nature of domain walls result in a triple point formation at the junction of chiral and achiral domain walls. The unconventional nature of the domain walls with triple point pairs may result in unique electrostatic and magnetic properties potentially useful for quantum sensing applications.
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Affiliation(s)
- Sandhya Susarla
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, 94720, CA, USA.
- Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, 94720, CA, USA.
- School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, 85280, AZ, USA.
| | - Shanglin Hsu
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, 94720, CA, USA
- Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, 94720, CA, USA
| | - Fernando Gómez-Ortiz
- Departmento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Cantabria Campus Internacional Santander, Santander, 39005, Spain
| | - Pablo García-Fernández
- Departmento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Cantabria Campus Internacional Santander, Santander, 39005, Spain
| | - Benjamin H Savitzky
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, 94720, CA, USA
| | - Sujit Das
- Materials Research Centre, Indian Institute of Science, Bangalore, 560012, Karnataka, India
| | - Piush Behera
- Department of Materials Science & Engineering, University of California, Berkeley, 94720, CA, USA
| | - Javier Junquera
- Departmento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Cantabria Campus Internacional Santander, Santander, 39005, Spain
| | - Peter Ercius
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, 94720, CA, USA
| | - Ramamoorthy Ramesh
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, 94720, CA, USA.
- Materials Sciences Division, Lawrence Berkeley Laboratory, Berkeley, 94720, CA, USA.
- Department of Physics, University of California, Berkeley, Berkeley, 94720, CA, USA.
- Department of Physics, Rice University, Houston, 77005, TX, USA.
- Department of Materials Science and Nanoengineering, Houston, 77005, TX, USA.
| | - Colin Ophus
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, 94720, CA, USA.
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9
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Das S, McCarter MR, Gómez-Ortiz F, Tang YL, Hong Z, Ghosh A, Shafer P, García-Fernández P, Junquera J, Martin LW, Ramesh R. Pure Chiral Polar Vortex Phase in PbTiO 3/SrTiO 3 Superlattices with Tunable Circular Dichroism. NANO LETTERS 2023. [PMID: 37449842 DOI: 10.1021/acs.nanolett.3c01744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
Nontrivial polarization textures have been demonstrated in ferroelectric/dielectric superlattices, where the electrostatic, elastic, and different gradient energies compete in a delicate balance. When PbTiO3/SrTiO3 superlattices are grown on DyScO3, the coexistence of ferroelectric domains and vortex structure is observed for n = 12-20 unit cells. Here, we report an approach to achieve single-phase vortex structures in superlattices by controlling the epitaxial strain using Sr1.04Al0.12Ga0.35Ta0.50O3 substrates. The domain width follows Kittel's law with the thickness of the ferroelectric PbTiO3 layers. A phase transition from vortex to a disordered phase with temperature is characterized by the correlation length. Resonant soft X-ray diffraction circular dichroism at the titanium L-edge reveals enhanced chirality with the thickness of the ferroelectric layer. These results are supported by second-principles simulations, which demonstrate that the integrated helicity increases with n. The stabilization of chiral single-phase polar vortices in ferroelectric/dielectric superlattices can enable novel optoelectronic devices with enhanced ferroelectric-light interaction.
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Affiliation(s)
- Sujit Das
- Materials Research Centre, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Margaret R McCarter
- Department of Materials Science & Engineering, University of California, Berkeley, California 94720, United States
- Department of Physics, University of California, Berkeley, California 94720, United States
| | - Fernando Gómez-Ortiz
- Departamento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Avenida de los Castros s/n, E-39005 Santander, Spain
| | - Yun-Long Tang
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Zijian Hong
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang 310027, China
| | - Anirban Ghosh
- Department of Materials Science & Engineering, University of California, Berkeley, California 94720, United States
| | - Padraic Shafer
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Pablo García-Fernández
- Departamento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Avenida de los Castros s/n, E-39005 Santander, Spain
| | - Javier Junquera
- Departamento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Avenida de los Castros s/n, E-39005 Santander, Spain
| | - Lane W Martin
- Department of Materials Science & Engineering, University of California, Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Ramamoorthy Ramesh
- Department of Materials Science & Engineering, University of California, Berkeley, California 94720, United States
- Department of Physics, University of California, Berkeley, California 94720, United States
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department of Materials Science and Nanoengineering, Department of Physics and Astronomy, Rice University, Houston, Texas 77251, United States
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10
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Govinden V, Tong P, Guo X, Zhang Q, Mantri S, Seyfouri MM, Prokhorenko S, Nahas Y, Wu Y, Bellaiche L, Sun T, Tian H, Hong Z, Valanoor N, Sando D. Ferroelectric solitons crafted in epitaxial bismuth ferrite superlattices. Nat Commun 2023; 14:4178. [PMID: 37443322 DOI: 10.1038/s41467-023-39841-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 06/29/2023] [Indexed: 07/15/2023] Open
Abstract
In ferroelectrics, complex interactions among various degrees of freedom enable the condensation of topologically protected polarization textures. Known as ferroelectric solitons, these particle-like structures represent a new class of materials with promise for beyond-CMOS technologies due to their ultrafine size and sensitivity to external stimuli. Such polarization textures have scarcely been demonstrated in multiferroics. Here, we present evidence for ferroelectric solitons in (BiFeO3)/(SrTiO3) superlattices. High-resolution piezoresponse force microscopy and Cs-corrected high-angle annular dark-field scanning transmission electron microscopy reveal a zoo of topologies, and polarization displacement mapping of planar specimens reveals center-convergent/divergent topological defects as small as 3 nm. Phase-field simulations verify that some of these structures can be classed as bimerons with a topological charge of ±1, and first-principles-based effective Hamiltonian computations show that the coexistence of such structures can lead to non-integer topological charges, a first observation in a BiFeO3-based system. Our results open new opportunities in multiferroic topotronics.
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Affiliation(s)
- Vivasha Govinden
- School of Materials Science and Engineering, University of New South Wales Sydney, Kensington, NSW, Australia
| | - Peiran Tong
- Center of Electron Microscopy, School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiangwei Guo
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, China
- Institute of Advanced Semiconductors & Zhejiang Provincial Key Laboratory of Power Semiconductor Materials and Devices, Hangzhou Innovation Center, Zhejiang University, Hangzhou, Zhejiang, China
- Cyrus Tang Center for Sensor Materials and Applications, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, China
| | - Qi Zhang
- School of Materials Science and Engineering, University of New South Wales Sydney, Kensington, NSW, Australia
| | - Sukriti Mantri
- Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, USA
| | - Mohammad Moein Seyfouri
- School of Materials Science and Engineering, University of New South Wales Sydney, Kensington, NSW, Australia
- Solid State and Elemental Analysis Unit, Mark Wainwright Analytical Center, University of New South Wales, Sydney, NSW, Australia
| | - Sergei Prokhorenko
- Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, USA
| | - Yousra Nahas
- Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, USA
| | - Yongjun Wu
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, China
- Cyrus Tang Center for Sensor Materials and Applications, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, China
| | - Laurent Bellaiche
- Physics Department and Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, AR, USA
| | - Tulai Sun
- Center of Electron Microscopy, School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, China
- Center for Electron Microscopy, State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology and College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, Zhejiang, China
| | - He Tian
- Center of Electron Microscopy, School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, China.
- School of Physics and Microelectronics, Zhengzhou University, Zhengzhou, Henan, China.
| | - Zijian Hong
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, China.
- Cyrus Tang Center for Sensor Materials and Applications, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Nagarajan Valanoor
- School of Materials Science and Engineering, University of New South Wales Sydney, Kensington, NSW, Australia.
| | - Daniel Sando
- School of Materials Science and Engineering, University of New South Wales Sydney, Kensington, NSW, Australia.
- School of Physical and Chemical Sciences, University of Canterbury, Christchurch, New Zealand.
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11
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Gong FH, Tang YL, Wang YJ, Chen YT, Wu B, Yang LX, Zhu YL, Ma XL. Absence of critical thickness for polar skyrmions with breaking the Kittel's law. Nat Commun 2023; 14:3376. [PMID: 37291226 PMCID: PMC10250330 DOI: 10.1038/s41467-023-39169-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Accepted: 05/31/2023] [Indexed: 06/10/2023] Open
Abstract
The period of polar domain (d) in ferroics was commonly believed to scale with corresponding film thicknesses (h), following the classical Kittel's law of d ∝ [Formula: see text]. Here, we have not only observed that this relationship fails in the case of polar skyrmions, where the period shrinks nearly to a constant value, or even experiences a slight increase, but also discovered that skyrmions have further persisted in [(PbTiO3)2/(SrTiO3)2]10 ultrathin superlattices. Both experimental and theoretical results indicate that the skyrmion periods (d) and PbTiO3 layer thicknesses in superlattice (h) obey the hyperbolic function of d = Ah + [Formula: see text] other than previous believed, simple square root law. Phase-field analysis indicates that the relationship originates from the different energy competitions of the superlattices with PbTiO3 layer thicknesses. This work exemplified the critical size problems faced by nanoscale ferroelectric device designing in the post-Moore era.
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Affiliation(s)
- Feng-Hui Gong
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang, 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Wenhua Road 72, Shenyang, 110016, China
| | - Yun-Long Tang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang, 110016, China
| | - Yu-Jia Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang, 110016, China
| | - Yu-Ting Chen
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang, 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Wenhua Road 72, Shenyang, 110016, China
| | - Bo Wu
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan, 523808, Guangdong, China
| | - Li-Xin Yang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang, 110016, China
| | - Yin-Lian Zhu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang, 110016, China.
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan, 523808, Guangdong, China.
| | - Xiu-Liang Ma
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang, 110016, China.
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan, 523808, Guangdong, China.
- Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China.
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12
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Yang T, Dai C, Chen LQ. Thermodynamics of Light-Induced Nanoscale Polar Structures in Ferroelectric Superlattices. NANO LETTERS 2023; 23:2551-2556. [PMID: 36971545 DOI: 10.1021/acs.nanolett.2c04586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
We study the thermodynamics of nanoscale polar structures in PbTiO3/SrTiO3 ferroelectric superlattices induced by above-bandgap optical excitation using a phase-field model explicitly considering both structural and electronic processes. We demonstrate that the light-excited carriers provide the charge compensation of polarization bound charges and the lattice thermal energy, both of which are key to the thermodynamic stabilization of a previously observed supercrystal, a three-dimensionally periodic nanostructure, within a window of substrate strains, while different mechanical and electrical boundary conditions can stabilize a number of other nanoscale polar structures by balancing the competing short-range exchange interactions responsible for the domain wall energy and long-range electrostatic and elastic interactions. The insights into the light-induced formation and richness of nanoscale structures from this work offer theoretical guidance for exploring and manipulating the thermodynamic stability of nanoscale polar structures employing a combination of thermal, mechanical, and electrical stimuli as well as light.
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Affiliation(s)
- Tiannan Yang
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Cheng Dai
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Long-Qing Chen
- Department of Materials Science and Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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13
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Liang Z, Song D, Ge B. Optimizing experimental parameters of integrated differential phase contrast (iDPC) for atomic resolution imaging. Ultramicroscopy 2023; 246:113686. [PMID: 36682324 DOI: 10.1016/j.ultramic.2023.113686] [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: 06/25/2022] [Revised: 11/30/2022] [Accepted: 01/16/2023] [Indexed: 01/19/2023]
Abstract
Integrated differential phase contrast scanning transmission electron microscopy (iDPC-STEM) technique has been well developed for studying atomic structures at sub-Å resolution with the capability of simultaneously imaging heavy and light atoms even at an extremely low electron dose. As a direct phase contrast imaging technique, atomic resolution iDPC-STEM is sensitive to the imaging conditions. Although great achievements have been made both in aspect of theory and experiments, the influence of experimental parameters on the contrast of atomic resolution iDPC-STEM images has not been systematically investigated. Here, we perform the iDPC-STEM simulations on the prototypical example of SrTiO3 with respect to the routine experimental factors, including the defocus, specimen thickness, accelerating voltage, convergence angle, collection angle, sample tilt and electron dose. Through the evaluation of image contrast and atom column intensity, the parameters are discussed to improve the image contrast and the visibility of light elements. Moreover, the dose-dependent simulations demonstrate the advantage of low dose iDPC-STEM imaging over other conventional STEM modes. Our results provide a practical guideline to experimentally obtain accessible atomic resolution iDPC-STEM images.
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Affiliation(s)
- Zhiyao Liang
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Dongsheng Song
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
| | - Binghui Ge
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Key Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of Education, Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China.
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14
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Li YQ, Wang P, Zhang H, Zhang H, Fu LB. Nonabelian Ginzburg-Landau theory for ferroelectrics. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2023; 35:155702. [PMID: 36731170 DOI: 10.1088/1361-648x/acb89d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 02/01/2023] [Indexed: 06/18/2023]
Abstract
The Ginzburg-Landau theory, which was introduced to phenomenologically describe the destruction of superconductivity by a magnetic field at the beginning, has brought up much more knowledge beyond the original one as a mean-field theory of thermodynamics states. There the complex order parameter plays an important role. Here we propose a macroscopic theory to describe the features of ferroelectrics by a two-component complex order parameter coupled to nonabelian gauge potentials that provide more freedom to reflect interplays between different measurables. Within this theoretical framework, some recently discovered empirical static and time-independent phenomena, such as vortex, anti-vortex, spiral orders can be obtained as solutions for different gauge potentials. It is expected to bring in a new angle of view with more elucidation than the traditional one that takes the polarization as order parameter.
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Affiliation(s)
- You-Quan Li
- Chern Institute of Mathematics, Nankai University, Weijin Road 94, Tianjin 300071, People's Republic of China
- School of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China
- Collaborative Innovation Center of Advanced Microstructure, Nanjing University, Nanjing 210008, People's Republic of China
| | - Pei Wang
- Department of Physics, Zhejiang Normal University, Jinhua 321004, People's Republic of China
| | - Hua Zhang
- Center for Advanced Material Diagnostic Technology, Shenzhen Technology University, Shenzhen 518118, People's Republic of China
| | - Hong Zhang
- School of Physics, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Li-Bin Fu
- Graduate School of China Academy of Engineering Physics, Beijing 100193, People's Republic of China
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15
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Yao W, Li D, Wei S, Liu X, Liu X, Wang W. Density Functional Theory Study on the Enhancement Mechanism of the Photocatalytic Properties of the g-C 3N 4/BiOBr(001) Heterostructure. ACS OMEGA 2022; 7:36479-36488. [PMID: 36278081 PMCID: PMC9583644 DOI: 10.1021/acsomega.2c04298] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 09/23/2022] [Indexed: 06/16/2023]
Abstract
The van der Waals heterostructures fabricated in two semiconductors are currently attracting considerable attention in various research fields. Our study uses density functional theory calculations within the Heyd-Scuseria-Ernzerhof hybrid functional to analyze the geometric structure and electronic structure of the g-C3N4/BiOBr(001) heterojunction in order to gain a better understanding of its photocatalytic properties. The calculated band alignments show that g-C3N4/BiOBr can function as a type-II heterojunction. In this heterojunction, the electrons and holes can effectively be separated at the interface. Moreover, we find that the electronic structure and band alignment of g-C3N4/BiOBr(001) can be tuned using external electric fields. It is also noteworthy that the optical absorption peak in the visible region is enhanced under the action of the electric field. The electric field may even improve the optical properties of the g-C3N4/BiOBr(001) heterostructure. Given the results of our calculations, it seems that g-C3N4/BiOBr(001) may be significantly superior to visible light photocatalysis.
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Affiliation(s)
- Wenzhi Yao
- Department
of Environmental and Municipal Engineering, North China University of Water Conservancy and Electric Power, Zhengzhou450011, China
| | - Dongying Li
- Department
of Environmental and Municipal Engineering, North China University of Water Conservancy and Electric Power, Zhengzhou450011, China
| | - Shuai Wei
- Department
of Environmental and Municipal Engineering, North China University of Water Conservancy and Electric Power, Zhengzhou450011, China
| | - Xiaoqing Liu
- Department
of Environmental and Municipal Engineering, North China University of Water Conservancy and Electric Power, Zhengzhou450011, China
| | - Xuefei Liu
- College
of Physics and Electronic Science, Guizhou
Normal University, Guiyang550025, China
| | - Wentao Wang
- College
of Physics and Electronic Science, Guizhou
Normal University, Guiyang550025, China
- Guizhou
Provincial Key Laboratory of Computational Nano-Material Science, Guizhou Education University, Guiyang550018, China
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16
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Zhu R, Jiang Z, Zhang X, Zhong X, Tan C, Liu M, Sun Y, Li X, Qi R, Qu K, Liu Z, Wu M, Li M, Huang B, Xu Z, Wang J, Liu K, Gao P, Wang J, Li J, Bai X. Dynamics of Polar Skyrmion Bubbles under Electric Fields. PHYSICAL REVIEW LETTERS 2022; 129:107601. [PMID: 36112449 DOI: 10.1103/physrevlett.129.107601] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 06/23/2022] [Accepted: 08/11/2022] [Indexed: 06/15/2023]
Abstract
Room-temperature polar skyrmions, which have been recently discovered in oxide superlattice, have received considerable attention for their potential applications in nanoelectronics owing to their nanometer size, emergent chirality, and negative capacitance. For practical applications, their manipulation using external stimuli is a prerequisite. Herein, we study the dynamics of individual polar skyrmions at the nanoscale via in situ scanning transmission electron microscopy. By monitoring the electric-field-driven creation, annihilation, shrinkage, and expansion of topological structures in real space, we demonstrate the reversible transformation among skyrmion bubbles, elongated skyrmions, and monodomains. The underlying mechanism and interactions are discussed in conjunction with phase-field simulations. The electrical manipulation of nanoscale polar skyrmions allows the tuning of their dielectric permittivity at the atomic scale, and the detailed knowledge of their phase transition behaviors provides fundamentals for their applications in nanoelectronics.
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Affiliation(s)
- Ruixue Zhu
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Zhexin Jiang
- Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Xinxin Zhang
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Xiangli Zhong
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Congbing Tan
- Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials, School of Physics and Electronics, Hunan University of Science and Technology, Xiangtan 411201, Hunan, China
| | - Mingwei Liu
- Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials, School of Physics and Electronics, Hunan University of Science and Technology, Xiangtan 411201, Hunan, China
| | - Yuanwei Sun
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Xiaomei Li
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Ruishi Qi
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Ke Qu
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Zhetong Liu
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Mei Wu
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Mingqiang Li
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, Peking University, Beijing 100871, China
| | - Boyuan Huang
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
| | - Zhi Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Jinbin Wang
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, Hunan, China
| | - Kaihui Liu
- State Key Laboratory for Artificial Microstructure & Mesoscopic Physics, School of Physics, 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
| | - Peng Gao
- Electron Microscopy Laboratory and International Center for Quantum Materials, School of Physics, 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
| | - Jie Wang
- Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, Zhejiang, China
- Zhejiang Laboratory, Hangzhou 311100, Zhejiang, China
| | - Jiangyu Li
- Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices, Southern University of Science and Technology, Shenzhen 518055, Guangdong, China
| | - Xuedong Bai
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
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17
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Guo X, Zhou L, Roul B, Wu Y, Huang Y, Das S, Hong Z. Theoretical Understanding of Polar Topological Phase Transitions in Functional Oxide Heterostructures: A Review. SMALL METHODS 2022; 6:e2200486. [PMID: 35900067 DOI: 10.1002/smtd.202200486] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 06/15/2022] [Indexed: 06/15/2023]
Abstract
The exotic topological phase is attracting considerable attention in condensed matter physics and materials science over the past few decades due to intriguing physical insights. As a combination of "topology" and "ferroelectricity," the ferroelectric (polar) topological structures are a fertile playground for emergent phenomena and functionalities with various potential applications. Herein, the review starts with the universal concept of the polar topological phase and goes on to briefly discuss the important role of computational tools such as phase-field simulations in designing polar topological phases in oxide heterostructures. In particular, the history of the development of phase-field simulations for ferroelectric oxide heterostructures is highlighted. Then, the current research progress of polar topological phases and their emergent phenomena in ferroelectric functional oxide heterostructures is reviewed from a theoretical perspective, including the topological polar structures, the establishment of phase diagrams, their switching kinetics and interconnections, phonon dynamics, and various macroscopic properties. Finally, this review offers a perspective on the future directions for the discovery of novel topological phases in other ferroelectric systems and device design for next-generation electronic device applications.
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Affiliation(s)
- Xiangwei Guo
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027, China
- Institute of Advanced Semiconductors and Zhejiang Provincial Key Laboratory of Power Semiconductor Materials and Devices, Hangzhou Innovation Center, Zhejiang University, Hangzhou, Zhejiang, 311200, China
- Cyrus Tang Center for Sensor Materials and Applications, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, 310027, China
| | - Linming Zhou
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027, China
| | - Basanta Roul
- Materials Research Centre, Indian Institute of Science, Bangalore, 560012, India
- Central Research Laboratory, Bharat Electronics Limited, Bangalore, 560013, India
| | - Yongjun Wu
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027, China
- Cyrus Tang Center for Sensor Materials and Applications, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, 310027, China
| | - Yuhui Huang
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027, China
| | - Sujit Das
- Materials Research Centre, Indian Institute of Science, Bangalore, 560012, India
| | - Zijian Hong
- School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027, China
- Cyrus Tang Center for Sensor Materials and Applications, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou, Zhejiang, 310027, China
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18
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Aramberri H, Fedorova NS, Íñiguez J. Ferroelectric/paraelectric superlattices for energy storage. SCIENCE ADVANCES 2022; 8:eabn4880. [PMID: 35921413 PMCID: PMC9348786 DOI: 10.1126/sciadv.abn4880] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 06/16/2022] [Indexed: 06/09/2023]
Abstract
The polarization response of antiferroelectrics to electric fields is such that the materials can store large energy densities, which makes them promising candidates for energy storage applications in pulsed-power technologies. However, relatively few materials of this kind are known. Here, we consider ferroelectric/paraelectric superlattices as artificial electrostatically engineered antiferroelectrics. Specifically, using high-throughput second-principles calculations, we engineer PbTiO3/SrTiO3 superlattices to optimize their energy storage performance at room temperature (to maximize density and release efficiency) with respect to different design variables (layer thicknesses, epitaxial conditions, and stiffness of the dielectric layer). We obtain results competitive with the state-of-the-art antiferroelectric capacitors and reveal the mechanisms responsible for the optimal properties.
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Affiliation(s)
- Hugo Aramberri
- Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg
- Inter-Institutional Research Group Uni.lu-LIST on Ferroic Materials, 41 Rue du Brill, L-4422 Belvaux, Luxembourg
| | - Natalya S. Fedorova
- Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg
- Inter-Institutional Research Group Uni.lu-LIST on Ferroic Materials, 41 Rue du Brill, L-4422 Belvaux, Luxembourg
| | - Jorge Íñiguez
- Materials Research and Technology Department, Luxembourg Institute of Science and Technology, 5 Avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxembourg
- Inter-Institutional Research Group Uni.lu-LIST on Ferroic Materials, 41 Rue du Brill, L-4422 Belvaux, Luxembourg
- Department of Physics and Materials Science, University of Luxembourg, 41 Rue du Brill, L-4422 Belvaux, Luxembourg
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19
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Chiral structures of electric polarization vectors quantified by X-ray resonant scattering. Nat Commun 2022; 13:1769. [PMID: 35383159 PMCID: PMC8983710 DOI: 10.1038/s41467-022-29359-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 03/07/2022] [Indexed: 11/08/2022] Open
Abstract
Resonant elastic X-ray scattering (REXS) offers a unique tool to investigate solid-state systems providing spatial knowledge from diffraction combined with electronic information through the enhanced absorption process, allowing the probing of magnetic, charge, spin, and orbital degrees of spatial order together with electronic structure. A new promising application of REXS is to elucidate the chiral structure of electrical polarization emergent in a ferroelectric oxide superlattice in which the polarization vectors in the REXS amplitude are implicitly described through an anisotropic tensor corresponding to the quadrupole moment. Here, we present a detailed theoretical framework and analysis to quantitatively analyze the experimental results of Ti L-edge REXS of a polar vortex array formed in a PbTiO3/SrTiO3 superlattice. Based on this theoretical framework, REXS for polar chiral structures can become a useful tool similar to x-ray resonant magnetic scattering (XRMS), enabling a comprehensive study of both electric and magnetic REXS on the chiral structures. The polar chiral texture of the vortex or skyrmion structure in ferroelectric oxide PbTiO3/SrTiO3 superlattice attracts attention. Here, the authors report a theoretical framework to probe emergent chirality of electrical polarization textures.
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20
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Liu Y, Liu J, Pan H, Cheng X, Hong Z, Xu B, Chen LQ, Nan CW, Lin YH. Phase-Field Simulations of Tunable Polar Topologies in Lead-Free Ferroelectric/Paraelectric Multilayers with Ultrahigh Energy-Storage Performance. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2108772. [PMID: 35034410 DOI: 10.1002/adma.202108772] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 01/13/2022] [Indexed: 06/14/2023]
Abstract
Dielectric capacitors are emerging energy-storage components that require both high energy-storage density and high efficiency. The conventional approach to energy-storage enhancement is polar nanodomain engineering via chemical modification. Here, a new approach of domain engineering is proposed by exploiting the tunable polar topologies that have been observed recently in ferroelectric/paraelectric multilayer films. Using phase-field simulations, it is demonstrated that vortex, spiral, and in-plane polar structures can be stabilized in BiFeO3 /SrTiO3 (BFO/STO) multilayers by tailoring the strain state and layer thickness. Various switching dynamics are realized in these polar topologies, resulting in relaxor-ferroelectric-, antiferroelectric-, and paraelectric-like polarization behaviors, respectively. Ultrahigh energy-storage densities above 170 J cm-3 and efficiencies above 95% are achievable in STO/BFO/STO trilayers. This strategy should be generally implementable in other multilayer dielectrics and offers a new avenue to enhancing energy storage by tuning the polar topology and thus the polarization characteristics.
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Affiliation(s)
- Yiqian Liu
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, P. R. China
| | - Junfu Liu
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, P. R. China
| | - Hao Pan
- Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA
| | | | - Zijian Hong
- Laboratory of Dielectric Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027, P. R. China
| | - Ben Xu
- Graduate School of China Academy of Engineering Physics, Beijing, 100094, P. R. China
| | - Long-Qing Chen
- Department of Materials Science and Engineering and Materials Research Institute, The Pennsylvania State University, University Park, PA, 16802-5005, USA
| | - Ce-Wen Nan
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, P. R. China
| | - Yuan-Hua Lin
- State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, P. R. China
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21
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Dai C, Stoica VA, Das S, Hong Z, Martin LW, Ramesh R, Freeland JW, Wen H, Gopalan V, Chen LQ. Tunable Nanoscale Evolution and Topological Phase Transitions of a Polar Vortex Supercrystal. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2106401. [PMID: 34958699 DOI: 10.1002/adma.202106401] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Revised: 12/03/2021] [Indexed: 06/14/2023]
Abstract
Understanding the phase transitions and domain evolutions of mesoscale topological structures in ferroic materials is critical to realizing their potential applications in next-generation high-performance storage devices. Here, the behaviors of a mesoscale supercrystal are studied with 3D nanoscale periodicity and rotational topology phases in a PbTiO3 /SrTiO3 (PTO/STO) superlattice under thermal and electrical stimuli using a combination of phase-field simulations and X-ray diffraction experiments. A phase diagram of temperature versus polar state is constructed, showing the formation of the supercrystal from a mixed vortex and a-twin state and a temperature-dependent erasing process of a supercrystal returning to a classical a-twin structure. Under an in-plane electric field bias at room temperature, the vortex topology of the supercrystal irreversibly transforms to a new type of stripe-like supercrystal. Under an out-of-plane electric field, the vortices inside the supercrystal undergo a topological phase transition to polar skyrmions. These results demonstrate the potential for the on-demand manipulation of polar topology and transformations in supercrystals using electric fields. The findings provide a theoretical understanding that may be utilized to guide the design and control of mesoscale polar structures and to explore novel polar structures in other systems and their topological nature.
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Affiliation(s)
- Cheng Dai
- Department of Materials Science and Engineering and Materials Research Institute, Pennsylvania State University, University Park, PA, 16802, USA
| | - Vladimir Alexandru Stoica
- Department of Materials Science and Engineering and Materials Research Institute, Pennsylvania State University, University Park, PA, 16802, USA
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Sujit Das
- Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA
| | - Zijian Hong
- Lab of Dielectric Materials, School of Materials Science and Engineering, Zhejiang University, Hangzhou, 310027, China
| | - Lane W Martin
- Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA
| | - Ramamoorthy Ramesh
- Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA
| | - John W Freeland
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Haidan Wen
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL, 60439, USA
- Materials Science Division, Argonne National Laboratory, Argonne, IL, 60439, USA
| | - Venkatraman Gopalan
- Department of Materials Science and Engineering and Materials Research Institute, Pennsylvania State University, University Park, PA, 16802, USA
| | - Long-Qing Chen
- Department of Materials Science and Engineering and Materials Research Institute, Pennsylvania State University, University Park, PA, 16802, USA
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22
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Chen W, Dong Z, Chen H, Shen J, Du X, Dong F, Zhou T, Huang W, Wu Z, Liu W, Zhang Y. Control of upconversion luminescence by tailoring energy migration in doped perovskite superlattices. OPTICS LETTERS 2022; 47:1250-1253. [PMID: 35230339 DOI: 10.1364/ol.452482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 01/24/2022] [Indexed: 06/14/2023]
Abstract
We describe an experimental investigation of photon upconversion (UC) in a series of perovskite BaTiO3/SrTiO3 superlattices doped with different lanthanide compositions. We show that UC emission can be effectively enhanced by precisely incorporating a set of lanthanide ions into separated layers rather than homogeneously distributing the dopant ions in the host lattice. The use of an inert layer in the superlattice can suppress deleterious energy cross-relaxation. Furthermore, UC emission can be rendered by controlling the energy migration mediated by the Yb-doped sublattice. These results demonstrate the opportunity to modulate energy migration and transfer processes through the rational design of superlattice structures.
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23
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Gong FH, Chen YT, Zhu YL, Tang YL, Zhang H, Wang YJ, Wu B, Liu JQ, Shi TT, Yang LX, Li CJ, Feng YP, Ma XL. Thickness-Dependent Polar Domain Evolution in Strained, Ultrathin PbTiO 3 Films. ACS APPLIED MATERIALS & INTERFACES 2022; 14:9724-9733. [PMID: 35138804 DOI: 10.1021/acsami.1c20797] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Ferroelectric ultrathin films have great potential in electronic devices and device miniaturization with the innovation of technology. In the process of product commercialization, understanding the domain evolution and topological properties of ferroelectrics is a prerequisite for high-density storage devices. In this work, a series of ultrathin PbTiO3 (PTO) films with varying thicknesses were deposited on cubic KTaO3 substrates by pulsed laser deposition and were researched by Cs-corrected scanning transmission electron microscopy (STEM), reciprocal space mapping (RSM), and piezoresponse force microscopy (PFM). RSM experiments indicate the existence of a/c domains and show that the lattice constant varies continuously, which is further confirmed by atomic-scale STEM imaging. Diffraction contrast analysis clarifies that with the decrease in PTO film thickness, the critical thickness for the formation of a/c domains could be missing. When the thickness of PTO films is less than 6 nm, the domain configurations in the ultrathin PTO films are the coexistence of a/c domains and bowl-like topological structures, where the latter ones were identified as convergent and divergent types of meron. In addition, abundant 90° charged domain walls in these ultrathin PTO films were identified. PFM studies reveal clear ferroelectric properties for these ultrathin PTO films. These results may shed light on further understanding the domain evolution and topological properties in ultrathin ferroelectric PTO films.
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Affiliation(s)
- Feng-Hui Gong
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Wenhua Road 72, Shenyang 110016, China
| | - Yu-Ting Chen
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Wenhua Road 72, Shenyang 110016, China
| | - Yin-Lian Zhu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, China
| | - Yun-Long Tang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
| | - Heng Zhang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Wenhua Road 72, Shenyang 110016, China
| | - Yu-Jia Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
| | - Bo Wu
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, China
| | - Jia-Qi Liu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Wenhua Road 72, Shenyang 110016, China
| | - Tong-Tong Shi
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Wenhua Road 72, Shenyang 110016, China
| | - Li-Xin Yang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
| | - Chang-Ji Li
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
| | - Yan-Peng Feng
- Bay Area Center for Electron Microscopy, Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, China
| | - Xiu-Liang Ma
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
- State Key Lab of Advanced Processing and Recycling on Non-ferrous Metals, Lanzhou University of Technology, Langongping Road 287, Lanzhou 730050, China
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24
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Shimada T, Wang Y, Hamaguchi T, Kasai K, Masuda K, Van Lich L, Xu T, Wang J, Hirakata H. Emergence of non-trivial polar topologies hidden in singular stress field in SrTiO 3: topological strain-field engineering. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:505301. [PMID: 34547728 DOI: 10.1088/1361-648x/ac28c1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 09/21/2021] [Indexed: 06/13/2023]
Abstract
Discovery of non-trivial topological structures in condensed matters holds promise in novel technological paradigms. In contrast to ferromagnetics, where a variety of topological structures such as vortex, meron, and skyrmion have been discovered, only few topological structures can exist in ferroelectrics due to the lack of non-collinear interaction like the Dzyaloshinskii-Moriya interaction in ferromagnetics. Here, we demonstrate that polarization structures with a wide range of topological numbers (winding numbernfrom -3 to +1) can be mechanically excited and designed by the mode-I singular stress field formed near the crack-tip in incipient ferroelectric SrTiO3. Our phase-field simulations based on Ginzburg-Landau theory successfully reveals that the near-tip polar topology is driven by the flexoelectric coupling with intense strain gradient at the tip, while a variety of the far-field topological structures is triggered by a collaboration between the electrostrictive and flexoelectric effects. The strain (gradient) field analysis further shows that the unexpected topological characters are implied in the singular stress field, which develops a variety of polar topologies near the crack tip. Therefore, our work provides a novel insight into the unusual interplay between mechanical- and ferroelectric-topologies, i.e. 'topological strain-field engineering', which paves the way to the mechanical design of functional topologies in the matter.
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Affiliation(s)
- Takahiro Shimada
- Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Yu Wang
- Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Takayuki Hamaguchi
- Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Kohta Kasai
- Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Kairi Masuda
- Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan
| | - Le Van Lich
- School of Materials Science and Engineering, Hanoi University of Science and Technology, No 1, Dai Co Viet Street, Hanoi 100000, Vietnam
| | - Tao Xu
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, People's Republic of China
| | - Jie Wang
- Department of Engineering Mechanics & Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, School of Aeronautics and Astronautics, Zhejiang University, Hangzhou 310027, People's Republic of China
| | - Hiroyuki Hirakata
- Department of Mechanical Engineering and Science, Kyoto University, Nishikyo-ku, Kyoto 615-8540, Japan
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25
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Tan C, Dong Y, Sun Y, Liu C, Chen P, Zhong X, Zhu R, Liu M, Zhang J, Wang J, Liu K, Bai X, Yu D, Ouyang X, Wang J, Gao P, Luo Z, Li J. Engineering polar vortex from topologically trivial domain architecture. Nat Commun 2021; 12:4620. [PMID: 34330915 PMCID: PMC8324780 DOI: 10.1038/s41467-021-24922-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 07/15/2021] [Indexed: 11/08/2022] Open
Abstract
Topologically nontrivial polar structures are not only attractive for high-density data storage, but also for ultralow power microelectronics thanks to their exotic negative capacitance. The vast majority of polar structures emerging naturally in ferroelectrics, however, are topologically trivial, and there are enormous interests in artificially engineered polar structures possessing nontrivial topology. Here we demonstrate reconstruction of topologically trivial strip-like domain architecture into arrays of polar vortex in (PbTiO3)10/(SrTiO3)10 superlattice, accomplished by fabricating a cross-sectional lamella from the superlattice film. Using a combination of techniques for polarization mapping, atomic imaging, and three-dimensional structure visualization supported by phase field simulations, we reveal that the reconstruction relieves biaxial epitaxial strain in thin film into a uniaxial one in lamella, changing the subtle electrostatic and elastostatic energetics and providing the driving force for the polar vortex formation. The work establishes a realistic strategy for engineering polar topologies in otherwise ordinary ferroelectric superlattices.
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Affiliation(s)
- Congbing Tan
- Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials, School of Physics and Electronics, Hunan University of Science and Technology, Xiangtan, Hunan, China
- School of Materials Science and Engineering, Xiangtan University, Xiangtan, Hunan, China
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Yongqi Dong
- Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, China
| | - Yuanwei Sun
- International Center for Quantum Materials, Peking University, Beijing, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China
| | - Chang Liu
- Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, Hangzhou, Zhejiang, China
- Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province, School of Mechanics and Engineering, Southwest Jiaotong University, Chengdu, Sichuan, China
| | - Pan Chen
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Xiangli Zhong
- School of Materials Science and Engineering, Xiangtan University, Xiangtan, Hunan, China
| | - Ruixue Zhu
- International Center for Quantum Materials, Peking University, Beijing, China
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China
| | - Mingwei Liu
- Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials, School of Physics and Electronics, Hunan University of Science and Technology, Xiangtan, Hunan, China
| | - Jingmin Zhang
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China
| | - Jinbin Wang
- School of Materials Science and Engineering, Xiangtan University, Xiangtan, Hunan, China
| | - Kaihui Liu
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China
- Collaborative Innovation Centre of Quantum Matter, Beijing, China
| | - Xuedong Bai
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing, China
| | - Dapeng Yu
- Collaborative Innovation Centre of Quantum Matter, Beijing, China
- State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing, China
- Shenzhen Key Laboratory of Quantum Science and Engineering, Shenzhen, Guangdong, China
| | - Xiaoping Ouyang
- School of Materials Science and Engineering, Xiangtan University, Xiangtan, Hunan, China
| | - Jie Wang
- Department of Engineering Mechanics, School of Aeronautics and Astronautics, Zhejiang University, Hangzhou, Zhejiang, China.
- Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Peng Gao
- International Center for Quantum Materials, Peking University, Beijing, China.
- Electron Microscopy Laboratory, School of Physics, Peking University, Beijing, China.
- Collaborative Innovation Centre of Quantum Matter, Beijing, China.
- Interdisciplinary Institute of Light-Element Quantum Materials and Research Center for Light-Element Advanced Materials, Peking University, Beijing, China.
| | - Zhenlin Luo
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, China.
| | - Jiangyu Li
- Department of Materials Science and Engineering, Southern University of Science and Technology, Shenzhen, Guangdong, China.
- Shenzhen Key Laboratory of Nanobiomechanics, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China.
- Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices, Southern University of Science and Technology, Shenzhen, Guangdong, China.
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26
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Tang Y, Zhu Y, Wu B, Wang Y, Yang L, Feng Y, Zou M, Geng W, Ma X. Periodic Polarization Waves in a Strained, Highly Polar Ultrathin SrTiO 3. NANO LETTERS 2021; 21:6274-6281. [PMID: 34252283 DOI: 10.1021/acs.nanolett.1c02117] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
SrTiO3 is generally paraelectric with centrosymmetric structure exhibiting unique quantum fluctuation related ferroelectricity. Here we reveal highly polar and periodic polarization waves in SrTiO3 at room temperature, which is stabilized by periodic tensile strains in a sandwiched PbTiO3/SrTiO3/PbTiO3 structure. Scanning transmission electron microscopy reveals that periodic a/c domain structures in PbTiO3 layers exert unique periodic tensile strains in the ultrathin SrTiO3 layer and consequently make the highly polar and periodic states of SrTiO3. The as-received polar SrTiO3 layer features peak polar ion displacement of ∼0.01 nm and peak tetragonality of ∼1.07. These peak values are larger than previous results, which are comparable to that of bulk ferroelectric PbTiO3. Our results suggest that it is possible to integrate large and periodic strain state in oxide films with exotic properties, which in turn could be useful in optical applications and information addressing when used as memory unit.
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Affiliation(s)
- Yunlong Tang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, 110016 Shenyang, China
| | - Yinlian Zhu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, 110016 Shenyang, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Bo Wu
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Yujia Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, 110016 Shenyang, China
| | - Lixin Yang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, 110016 Shenyang, China
| | - Yanpeng Feng
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Minjie Zou
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Wanrong Geng
- Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
- Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Xiuliang Ma
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, 110016 Shenyang, China
- State Key Lab of Advanced Processing and Recycling on Non-ferrous Metals, Lanzhou University of Technology, Langongping Road 287, 730050 Lanzhou, China
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