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Deng L, Zhang W, Lin H, Xiang L, Xu Y, Wang Y, Li Q, Zhu Y, Zhou X, Wang W, Yin L, Guo H, Tian C, Shen J. Polarization-dependent photoinduced metal-insulator transitions in manganites. Sci Bull (Beijing) 2024; 69:183-189. [PMID: 38057234 DOI: 10.1016/j.scib.2023.11.058] [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: 10/06/2023] [Revised: 11/10/2023] [Accepted: 11/23/2023] [Indexed: 12/08/2023]
Abstract
In correlated oxides, collaborative manipulation on light intensity, wavelength, pulse duration and polarization has yielded many exotic discoveries, such as phase transitions and novel quantum states. In view of potential optoelectronic applications, tailoring long-lived static properties by light-induced effects is highly desirable. So far, the polarization state of light has rarely been reported as a control parameter for this purpose. Here, we report polarization-dependent metal-to-insulator transition (MIT) in phase-separated manganite thin films, introducing a new degree of freedom to control static MIT. Specifically, we observed giant photoinduced resistance jumps with striking features: (1) a single resistance jump occurs upon a linearly polarized light incident with a chosen polarization angle, and a second resistance jump occurs when the polarization angle changes; (2) the amplitude of the second resistance jump depends sensitively on the actual change of the polarization angles. Linear transmittance measurements reveal that the origin of the above phenomena is closely related to the coexistence of anisotropic micro-domains. Our results represent a first step to utilize light polarization as an active knob to manipulate static phase transitions, pointing towards new pathways for nonvolatile optoelectronic devices and sensors.
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Affiliation(s)
- Lina Deng
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China
| | - Weiye Zhang
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China
| | - Hanxuan Lin
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China
| | - Lifen Xiang
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China
| | - Ying Xu
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China
| | - Yadi Wang
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China
| | - Qiang Li
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China
| | - Yinyan Zhu
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China; Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai 201210, China
| | - Xiaodong Zhou
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China; Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai 201210, China
| | - Wenbin Wang
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China; Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai 201210, China
| | - Lifeng Yin
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China; Shanghai Research Center for Quantum Sciences, Shanghai 201315, China; Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai 201210, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China
| | - Hangwen Guo
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China; Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai 201210, China.
| | - Chuanshan Tian
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China.
| | - Jian Shen
- State Key Laboratory of Surface Physics, Institute for Nanoelectronic Devices and Quantum Computing, and Department of Physics, Fudan University, Shanghai 200433, China; Shanghai Research Center for Quantum Sciences, Shanghai 201315, China; Zhangjiang Fudan International Innovation Center, Fudan University, Shanghai 201210, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China; Shanghai Branch, CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, Shanghai 201315, China.
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Fukaya R, Adachi JI, Nakao H, Yamasaki Y, Tabata C, Nozawa S, Ichiyanagi K, Ishii Y, Kimura H, Adachi SI. Time-resolved resonant soft X-ray scattering combined with MHz synchrotron X-ray and laser pulses at the Photon Factory. JOURNAL OF SYNCHROTRON RADIATION 2022; 29:1414-1419. [PMID: 36345749 PMCID: PMC9641559 DOI: 10.1107/s1600577522008724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 08/31/2022] [Indexed: 06/16/2023]
Abstract
A picosecond pump-probe resonant soft X-ray scattering measurement system has been developed at the Photon Factory storage ring for highly efficient data collection. A high-repetition-rate high-power compact laser system has been installed to improve efficiency via flexible data acquisition to a sub-MHz frequency in time-resolved experiments. Data are acquired by gating the signal of a channel electron multiplier with a pulse-counting mode capable of discriminating single-bunch soft X-ray pulses in the dark gap of the hybrid operation mode in the storage ring. The photoinduced dynamics of magnetic order for multiferroic manganite SmMn2O5 are clearly demonstrated by the detection of transient changes in the resonant soft X-ray scattering intensity around the Mn LIII- and O K-edges.
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Affiliation(s)
- Ryo Fukaya
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan
| | - Jun-ichi Adachi
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan
- Graduate University for Advanced Studies (SOKENDAI), Tsukuba, Ibaraki 305-0801, Japan
| | - Hironori Nakao
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan
- Graduate University for Advanced Studies (SOKENDAI), Tsukuba, Ibaraki 305-0801, Japan
| | - Yuichi Yamasaki
- Research and Services Division of Materials Data and Integrated System, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan
| | - Chihiro Tabata
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, Kumatori, Osaka 590-0494, Japan
| | - Shunsuke Nozawa
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan
- Graduate University for Advanced Studies (SOKENDAI), Tsukuba, Ibaraki 305-0801, Japan
| | - Kouhei Ichiyanagi
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan
| | - Yuta Ishii
- Department of Physics, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Hiroyuki Kimura
- Department of Physics, Tohoku University, Sendai, Miyagi 980-8578, Japan
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - Shin-ichi Adachi
- Institute of Materials Structure Science, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801, Japan
- Graduate University for Advanced Studies (SOKENDAI), Tsukuba, Ibaraki 305-0801, Japan
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Andrade X, Pemmaraju CD, Kartsev A, Xiao J, Lindenberg A, Rajpurohit S, Tan LZ, Ogitsu T, Correa AA. Inq, a Modern GPU-Accelerated Computational Framework for (Time-Dependent) Density Functional Theory. J Chem Theory Comput 2021; 17:7447-7467. [PMID: 34726888 DOI: 10.1021/acs.jctc.1c00562] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present inq, a new implementation of density functional theory (DFT) and time-dependent DFT (TDDFT) written from scratch to work on graphic processing units (GPUs). Besides GPU support, inq makes use of modern code design features and takes advantage of newly available hardware. By designing the code around algorithms, rather than against specific implementations and numerical libraries, we aim to provide a concise and modular code. The result is a fairly complete DFT/TDDFT implementation in roughly 12 000 lines of open-source C++ code representing a modular platform for community-driven application development on emerging high-performance computing architectures.
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Affiliation(s)
- Xavier Andrade
- Quantum Simulations Group, Lawrence Livermore National Laboratory, Livermore, California 94551, United States
| | - Chaitanya Das Pemmaraju
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Alexey Kartsev
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Jun Xiao
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Aaron Lindenberg
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Sangeeta Rajpurohit
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Liang Z Tan
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Tadashi Ogitsu
- Quantum Simulations Group, Lawrence Livermore National Laboratory, Livermore, California 94551, United States
| | - Alfredo A Correa
- Quantum Simulations Group, Lawrence Livermore National Laboratory, Livermore, California 94551, United States
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4
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Soft X-ray Lensless Imaging in Reflection Mode. PHOTONICS 2021. [DOI: 10.3390/photonics8120569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We report on the development and implementation of methodologies dedicated to soft X-ray imaging by coherent scattering in reflection mode. Two complementary approaches are tested, based on Fourier transform holography and on ptychography. A new method for designing holographic masks has been developed. Our results represent a feasibility test and highlight the potential and limitations of imaging in reflection mode. Reflectivity is less efficient than transmission at soft X-ray wavelengths, hampering the acquisition of good quality images. Nonetheless, it has the potential to image a wider set of samples, notably those that are not transparent to soft X-rays. Although the images obtained so far are of modest quality, these results are extremely encouraging for continuing the development of coherent soft X-ray imaging in reflection mode.
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Guang Y, Peng Y, Yan Z, Liu Y, Zhang J, Zeng X, Zhang S, Zhang S, Burn DM, Jaouen N, Wei J, Xu H, Feng J, Fang C, van der Laan G, Hesjedal T, Cui B, Zhang X, Yu G, Han X. Electron Beam Lithography of Magnetic Skyrmions. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2020; 32:e2003003. [PMID: 32812294 DOI: 10.1002/adma.202003003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/27/2020] [Indexed: 05/08/2023]
Abstract
The emergence of magnetic skyrmions, topological spin textures, has aroused tremendous interest in studying the rich physics related to their topology. While skyrmions promise high-density and energy-efficient magnetic memory devices for information technology, the manifestation of their nontrivial topology through single skyrmions and ordered and disordered skyrmion lattices could also give rise to many fascinating physical phenomena, such as chiral magnon and skyrmion glass states. Therefore, generating skyrmions at designated locations on a large scale, while controlling the skyrmion patterns, is the key to advancing topological magnetism. Here, a new, yet general, approach to the "printing" of skyrmions with zero-field stability in arbitrary patterns on a massive scale in exchange-biased magnetic multilayers is presented. By exploiting the fact that the antiferromagnetic order can be reconfigured by local thermal excitations, a focused electron beam with a graphic pattern generator to "print" skyrmions is used, which is referred to as skyrmion lithography. This work provides a route to design arbitrary skyrmion patterns, thereby establishing the foundation for further exploration of topological magnetism.
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Affiliation(s)
- Yao Guang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yong Peng
- Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou, 730000, China
| | - Zhengren Yan
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yizhou Liu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Junwei Zhang
- Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou, 730000, China
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Xue Zeng
- School of Mathematics and Physics, Lanzhou Jiaotong University, Lanzhou, 730070, China
| | - Senfu Zhang
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Shilei Zhang
- ShanghaiTech Laboratory for Topological Physics, ShanghaiTech University, Shanghai, 201210, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - David M Burn
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Nicolas Jaouen
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, Gif-sur-Yvette, 91192, France
| | - Jinwu Wei
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Hongjun Xu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Jiafeng Feng
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Chi Fang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Gerrit van der Laan
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, UK
| | - Thorsten Hesjedal
- Department of Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford, OX1 3PU, UK
| | - Baoshan Cui
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Xixiang Zhang
- Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal, 23955-6900, Saudi Arabia
| | - Guoqiang Yu
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
| | - Xiufeng Han
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing, 100190, China
- Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
- Songshan Lake Materials Laboratory, Dongguan, Guangdong, 523808, China
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6
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Ultrafast magnetic dynamics in insulating YBa 2Cu 3O 6.1 revealed by time resolved two-magnon Raman scattering. Nat Commun 2020; 11:2548. [PMID: 32439836 PMCID: PMC7242324 DOI: 10.1038/s41467-020-16275-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 04/24/2020] [Indexed: 11/08/2022] Open
Abstract
Measurement and control of magnetic order and correlations in real time is a rapidly developing scientific area relevant for magnetic memory and spintronics. In these experiments an ultrashort laser pulse (pump) is first absorbed by excitations carrying electric dipole moment. These then give their energy to the magnetic subsystem monitored by a time-resolved probe. A lot of progress has been made in investigations of ferromagnets but antiferromagnets are more challenging. Here, we introduce time-resolved two-magnon Raman scattering as a real time probe of magnetic correlations especially well-suited for antiferromagnets. Its application to the antiferromagnetic charge transfer insulator YBa2Cu3O6.1 revealed rapid demagnetization within 90 fs of photoexcitation. The relaxation back to thermal equilibrium is characterized by much slower timescales. We interpret these results in terms of slow relaxation of the charge sector and rapid equilibration of the magnetic sector to a prethermal state characterized by parameters that change slowly as the charge sector relaxes.
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7
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Creating zero-field skyrmions in exchange-biased multilayers through X-ray illumination. Nat Commun 2020; 11:949. [PMID: 32075968 PMCID: PMC7031520 DOI: 10.1038/s41467-020-14769-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 01/29/2020] [Indexed: 11/15/2022] Open
Abstract
Skyrmions, magnetic textures with topological stability, hold promises for high-density and energy-efficient information storage devices owing to their small size and low driving-current density. Precise creation of a single nanoscale skyrmion is a prerequisite to further understand the skyrmion physics and tailor skyrmion-based applications. Here, we demonstrate the creation of individual skyrmions at zero-field in an exchange-biased magnetic multilayer with exposure to soft X-rays. In particular, a single skyrmion with 100-nm size can be created at the desired position using a focused X-ray spot of sub-50-nm size. This single skyrmion creation is driven by the X-ray-induced modification of the antiferromagnetic order and the corresponding exchange bias. Furthermore, artificial skyrmion lattices with various arrangements can be patterned using X-ray. These results demonstrate the potential of accurate optical control of single skyrmion at sub-100 nm scale. We envision that X-ray could serve as a versatile tool for local manipulation of magnetic orders. Skyrmions are objects with whirled magnetization protected by their topology that can be created by different means, however, without control of their position. Here, the authors present a method exploiting x-rays to create skyrmions at the beam position allowing for creation of artificial skyrmion lattices.
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8
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Li J, Wang R, Guo H, Zhu Y, Cao Y, Liu J, Ding H, Wen H, Liu X. Recovery of photoexcited magnetic ordering in Sr 2IrO 4. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:255801. [PMID: 30897558 DOI: 10.1088/1361-648x/ab123d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The recovery of antiferromagnetic and lattice order of Sr2IrO4 upon laser excitation was measured by time-resolved x-ray diffraction on nanosecond time scales. The in situ measurements of both magnetic and lattice order parameters allow direct comparison of their time evolutions without ambiguity. We found that the magnetic order recovers with two time constants. The fast sub-nanosecond recovery is associated with the re-establishment of three dimensional antiferromagnetic order while the slow sub-nanosecond recovery agrees with the lattice cooling on tens of nanoseconds. The strong oscillating behavior of magnetic order during the long time recovery may be related to complicated dynamics of defect-pinned magnetic domains.
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Affiliation(s)
- Jiemin Li
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China. School of Physics, University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
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9
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Li J, Strand HUR, Werner P, Eckstein M. Theory of photoinduced ultrafast switching to a spin-orbital ordered hidden phase. Nat Commun 2018; 9:4581. [PMID: 30389918 PMCID: PMC6214932 DOI: 10.1038/s41467-018-07051-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 10/06/2018] [Indexed: 11/09/2022] Open
Abstract
Photo-induced hidden phases are often observed in materials with intertwined orders. Understanding the formation of these non-thermal phases is challenging and requires a resolution of the cooperative interplay between different orders on the ultra-short timescale. In this work, we demonstrate that non-equilibrium photo-excitations can induce a state with spin-orbital orders entirely different from the equilibrium state in the three-quarter-filled two-band Hubbard model. We identify a general mechanism governing the transition to the hidden state, which relies on a non-thermal partial melting of the intertwined orders mediated by photoinduced charge excitations in the presence of strong spin-orbital exchange interactions. Our study theoretically confirms the crucial role played by orbital degrees of freedom in the light-induced dynamics of strongly correlated materials and it shows that the switching to hidden states can be controlled already on the fs timescale of the electron dynamics. Ultrafast excitation of materials can cause the formation of hidden phases that are not accessible in thermal equilibrium. Li et al. identify and investigate theoretically a hidden phase that can be accessed in systems with intertwined spin and orbital-ordering such as KCuF3.
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Affiliation(s)
- Jiajun Li
- Department of Physics, University Erlangen-Nürnberg, 91058, Erlangen, Germany.
| | - Hugo U R Strand
- Center for Computational Quantum Physics, Flatiron Institute, 162 Fifth Avenue, New York, NY, 10010, USA.,Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211, Geneva 4, Switzerland.,Department of Physics, University of Fribourg, 1700, Fribourg, Switzerland
| | - Philipp Werner
- Department of Physics, University of Fribourg, 1700, Fribourg, Switzerland
| | - Martin Eckstein
- Department of Physics, University Erlangen-Nürnberg, 91058, Erlangen, Germany
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10
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Han Q, Millis A. Lattice Energetics and Correlation-Driven Metal-Insulator Transitions: The Case of Ca_{2}RuO_{4}. PHYSICAL REVIEW LETTERS 2018; 121:067601. [PMID: 30141680 DOI: 10.1103/physrevlett.121.067601] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 05/20/2018] [Indexed: 06/08/2023]
Abstract
This Letter uses density functional, dynamical mean field, and Landau-theory methods to elucidate the interplay of electronic and structural energetics in the Mott metal-insulator transition. A Landau-theory free energy is presented that incorporates the electronic energetics, the coupling of the electronic state to local distortions and the coupling of local distortions to long-wavelength strains. The theory is applied to Ca_{2}RuO_{4}. The change in lattice energy across the metal-insulator transition is comparable to the change in electronic energy. Important consequences are a strongly first order transition, a sensitive dependence of the phase boundary on pressure and that the geometrical constraints on in-plane lattice parameter associated with epitaxial growth on a substrate typically change the lattice energetics enough to eliminate the metal-insulator transition entirely.
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Affiliation(s)
- Qiang Han
- Department of Physics, Columbia University, New York, New York 10027, USA
| | - Andrew Millis
- Department of Physics, Columbia University, New York, New York 10027, USA
- The Center for Computational Quantum Physics, The Flatiron Institute, New York, New York 10010, USA
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11
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Porer M, Fechner M, Bothschafter EM, Rettig L, Savoini M, Esposito V, Rittmann J, Kubli M, Neugebauer MJ, Abreu E, Kubacka T, Huber T, Lantz G, Parchenko S, Grübel S, Paarmann A, Noack J, Beaud P, Ingold G, Aschauer U, Johnson SL, Staub U. Ultrafast Relaxation Dynamics of the Antiferrodistortive Phase in Ca Doped SrTiO_{3}. PHYSICAL REVIEW LETTERS 2018; 121:055701. [PMID: 30118273 DOI: 10.1103/physrevlett.121.055701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Indexed: 06/08/2023]
Abstract
The ultrafast dynamics of the octahedral rotation in Ca:SrTiO_{3} is studied by time-resolved x-ray diffraction after photoexcitation over the band gap. By monitoring the diffraction intensity of a superlattice reflection that is directly related to the structural order parameter of the soft-mode driven antiferrodistortive phase in Ca:SrTiO_{3}, we observe an ultrafast relaxation on a 0.2 ps timescale of the rotation of the oxygen octahedron, which is found to be independent of the initial temperature despite large changes in the corresponding soft-mode frequency. A further, much smaller reduction on a slower picosecond timescale is attributed to thermal effects. Time-dependent density-functional-theory calculations show that the fast response can be ascribed to an ultrafast displacive modification of the soft-mode potential towards the normal state induced by holes created in the oxygen 2p states.
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Affiliation(s)
- M Porer
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - M Fechner
- Max Planck Institute for the Structure and Dynamics of Matter, CFEL, 22761 Hamburg, Germany
- Materials Theory, ETH Zürich, 8093 Zürich, Switzerland
| | - E M Bothschafter
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - L Rettig
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
- Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - M Savoini
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - V Esposito
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - J Rittmann
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - M Kubli
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - M J Neugebauer
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - E Abreu
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - T Kubacka
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - T Huber
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - G Lantz
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - S Parchenko
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - S Grübel
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - A Paarmann
- Department of Physical Chemistry, Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - J Noack
- Department of Inorganic Chemistry, Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - P Beaud
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - G Ingold
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
| | - U Aschauer
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - S L Johnson
- Institute for Quantum Electronics, ETH Zürich, 8093 Zürich, Switzerland
| | - U Staub
- Swiss Light Source, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland
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12
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Pressacco F, Uhlíř V, Gatti M, Nicolaou A, Bendounan A, Arregi JA, Patel SKK, Fullerton EE, Krizmancic D, Sirotti F. Laser induced phase transition in epitaxial FeRh layers studied by pump-probe valence band photoemission. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2018; 5:034501. [PMID: 29888296 PMCID: PMC5966309 DOI: 10.1063/1.5027809] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 04/27/2018] [Indexed: 06/08/2023]
Abstract
We use time-resolved X-ray photoelectron spectroscopy to probe the electronic and magnetization dynamics in FeRh films after ultrafast laser excitations. We present experimental and theoretical results which investigate the electronic structure of FeRh during the first-order phase transition, identifying a clear signature of the magnetic phase. We find that a spin polarized feature at the Fermi edge is a fingerprint of the magnetic status of the system that is independent of the long-range ferromagnetic alignment of the magnetic domains. We use this feature to follow the phase transition induced by a laser pulse in a pump-probe experiment and find that the magnetic transition occurs in less than 50 ps and reaches its maximum in 100 ps.
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Affiliation(s)
| | | | | | - Alessandro Nicolaou
- Synchrotron SOLEIL, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - Azzedine Bendounan
- Synchrotron SOLEIL, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
| | - Jon Ander Arregi
- CEITEC BUT, Brno University of Technology, Purkyňova 123, 612 00 Brno, Czech Republic
| | - Sheena K K Patel
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093-0401, USA
| | - Eric E Fullerton
- Center for Memory and Recording Research, University of California, San Diego, La Jolla, California 92093-0401, USA
| | - Damjan Krizmancic
- Instituto Officina dei Materiali (IOM)-CNR, Laboratorio TASC, in Area Science Park S.S.14, Km 163.5, I34149 Trieste, Italy
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13
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Guo F, Zhang N, Jin W, Chang J. Model of ultrafast demagnetization driven by spin-orbit coupling in a photoexcited antiferromagnetic insulator Cr2O3. J Chem Phys 2017; 146:244502. [DOI: 10.1063/1.4989957] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Feng Guo
- College of Physics and Information Technology, Shaanxi Normal University, Xi’an 710119, China
| | - Na Zhang
- College of Physics and Information Technology, Shaanxi Normal University, Xi’an 710119, China
| | - Wei Jin
- College of Physics and Information Technology, Shaanxi Normal University, Xi’an 710119, China
| | - Jun Chang
- College of Physics and Information Technology, Shaanxi Normal University, Xi’an 710119, China
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14
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Liu M, Sternbach AJ, Basov DN. Nanoscale electrodynamics of strongly correlated quantum materials. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2017; 80:014501. [PMID: 27811387 DOI: 10.1088/0034-4885/80/1/014501] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Electronic, magnetic, and structural phase inhomogeneities are ubiquitous in strongly correlated quantum materials. The characteristic length scales of the phase inhomogeneities can range from atomic to mesoscopic, depending on their microscopic origins as well as various sample dependent factors. Therefore, progress with the understanding of correlated phenomena critically depends on the experimental techniques suitable to provide appropriate spatial resolution. This requirement is difficult to meet for some of the most informative methods in condensed matter physics, including infrared and optical spectroscopy. Yet, recent developments in near-field optics and imaging enabled a detailed characterization of the electromagnetic response with a spatial resolution down to 10 nm. Thus it is now feasible to exploit at the nanoscale well-established capabilities of optical methods for characterization of electronic processes and lattice dynamics in diverse classes of correlated quantum systems. This review offers a concise description of the state-of-the-art near-field techniques applied to prototypical correlated quantum materials. We also discuss complementary microscopic and spectroscopic methods which reveal important mesoscopic dynamics of quantum materials at different energy scales.
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Affiliation(s)
- Mengkun Liu
- Department of Physics, Stony Brook University, Stony Brook, NY 11794, USA
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15
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Wall S, Trigo M. Recent Developments in Ultrafast X-ray Techniques for Materials Science Applications. ACTA ACUST UNITED AC 2016. [DOI: 10.1080/08940886.2016.1220273] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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16
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Mankowsky R, Först M, Cavalleri A. Non-equilibrium control of complex solids by nonlinear phononics. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2016; 79:064503. [PMID: 27223639 DOI: 10.1088/0034-4885/79/6/064503] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We review some recent advances in the use of optical fields at terahertz frequencies to drive the lattice of complex materials. We will focus on the control of low energy collective properties of solids, which emerge on average when a high frequency vibration is driven and a new crystal structure induced. We first discuss the fundamentals of these lattice rearrangements, based on how anharmonic mode coupling transforms an oscillatory motion into a quasi-static deformation of the crystal structure. We then discuss experiments, in which selectively changing a bond angle turns an insulator into a metal, accompanied by changes in charge, orbital and magnetic order. We then address the case of light induced non-equilibrium superconductivity, a mysterious phenomenon observed in some cuprates and molecular materials when certain lattice vibrations are driven. Finally, we show that the dynamics of electronic and magnetic phase transitions in complex-oxide heterostructures follow distinctly new physical pathways in case of the resonant excitation of a substrate vibrational mode.
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Affiliation(s)
- Roman Mankowsky
- Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany
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17
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Dean MPM, Cao Y, Liu X, Wall S, Zhu D, Mankowsky R, Thampy V, Chen XM, Vale JG, Casa D, Kim J, Said AH, Juhas P, Alonso-Mori R, Glownia JM, Robert A, Robinson J, Sikorski M, Song S, Kozina M, Lemke H, Patthey L, Owada S, Katayama T, Yabashi M, Tanaka Y, Togashi T, Liu J, Rayan Serrao C, Kim BJ, Huber L, Chang CL, McMorrow DF, Först M, Hill JP. Ultrafast energy- and momentum-resolved dynamics of magnetic correlations in the photo-doped Mott insulator Sr2IrO4. NATURE MATERIALS 2016; 15:601-5. [PMID: 27159018 DOI: 10.1038/nmat4641] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Accepted: 04/07/2016] [Indexed: 05/07/2023]
Abstract
Measuring how the magnetic correlations evolve in doped Mott insulators has greatly improved our understanding of the pseudogap, non-Fermi liquids and high-temperature superconductivity. Recently, photo-excitation has been used to induce similarly exotic states transiently. However, the lack of available probes of magnetic correlations in the time domain hinders our understanding of these photo-induced states and how they could be controlled. Here, we implement magnetic resonant inelastic X-ray scattering at a free-electron laser to directly determine the magnetic dynamics after photo-doping the Mott insulator Sr2IrO4. We find that the non-equilibrium state, 2 ps after the excitation, exhibits strongly suppressed long-range magnetic order, but hosts photo-carriers that induce strong, non-thermal magnetic correlations. These two-dimensional (2D) in-plane Néel correlations recover within a few picoseconds, whereas the three-dimensional (3D) long-range magnetic order restores on a fluence-dependent timescale of a few hundred picoseconds. The marked difference in these two timescales implies that the dimensionality of magnetic correlations is vital for our understanding of ultrafast magnetic dynamics.
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Affiliation(s)
- M P M Dean
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - Y Cao
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - X Liu
- Beijing National Laboratory for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
- Collaborative Innovation Center of Quantum Matter, Beijing, China
| | - S Wall
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, 08860 Castelldefels (Barcelona), Spain
| | - D Zhu
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - R Mankowsky
- Max Planck Institute for the Structure and Dynamics of Matter, D-22761 Hamburg, Germany
- Center for Free Electron Laser Science, D-22761 Hamburg, Germany
| | - V Thampy
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - X M Chen
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - J G Vale
- London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, London WC1E 6BT, UK
| | - D Casa
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Jungho Kim
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - A H Said
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - P Juhas
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, New York 11973, USA
| | - R Alonso-Mori
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - J M Glownia
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - A Robert
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - J Robinson
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - M Sikorski
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - S Song
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - M Kozina
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - H Lemke
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - L Patthey
- SwissFEL, Paul Scherrer Institut, CH-5232 Villigen PSI, Switzerland
| | - S Owada
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | - T Katayama
- Japan Synchrotron Radiation Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - M Yabashi
- RIKEN SPring-8 Center, Sayo, Hyogo 679-5148, Japan
| | | | - T Togashi
- Japan Synchrotron Radiation Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - J Liu
- Department of Physics &Astronomy, University of Tennessee, Knoxville, Tennessee 37996, USA
| | - C Rayan Serrao
- Department of Electrical Engineering and Computer Sciences, University of California, Berkeley, California 94720, USA
| | - B J Kim
- Max Planck Institute for Solid State Research, D-70569 Stuttgart, Germany
| | - L Huber
- Institute for Quantum Electronics, ETH Zurich, CH-8093 Zurich, Switzerland
| | - C-L Chang
- Zernike Institute for Advanced Materials, University of Groningen, Groningen, NL 9747AG, The Netherlands
| | - D F McMorrow
- London Centre for Nanotechnology and Department of Physics and Astronomy, University College London, London WC1E 6BT, UK
| | - M Först
- Max Planck Institute for the Structure and Dynamics of Matter, D-22761 Hamburg, Germany
- Center for Free Electron Laser Science, D-22761 Hamburg, Germany
| | - J P Hill
- Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, New York 11973, USA
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18
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Li Y, Walko DA, Li Q, Liu Y, Rosenkranz S, Zheng H, Mitchell JF. Evidence of photo-induced dynamic competition of metallic and insulating phase in a layered manganite. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:495602. [PMID: 26575485 DOI: 10.1088/0953-8984/27/49/495602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We show evidence that the competition between the antiferromagetic metallic phase and the charge- and orbital-ordered insulating phase at the reentrant phase boundary of a layered manganite, La0.99Sr2.01Mn2O7, can be manipulated using ultrafast optical excitation. The time-dependent evolution of the Jahn-Teller superlattice reflection, which indicates the formation of the charge and orbital order, was measured at different laser fluences. The laser-induced enhancement and reduction the Jahn-Teller reflection intensity shows a reversal of sign between earlier (~10 ns) and later (~150 ns) time delays during the relaxation after photo excitation. This effect is consistent with a scenario whereby the laser excitation modulates the local competition between the metallic and the insulating phases.
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Affiliation(s)
- Yuelin Li
- Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439, USA
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19
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Terahertz field control of in-plane orbital order in La(0.5)Sr(1.5)MnO4. Nat Commun 2015; 6:8175. [PMID: 26381700 PMCID: PMC4595605 DOI: 10.1038/ncomms9175] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 07/27/2015] [Indexed: 11/20/2022] Open
Abstract
In-plane anisotropic ground states are ubiquitous in correlated solids such as pnictides, cuprates and manganites. They can arise from doping Mott insulators and compete with phases such as superconductivity; however, their origins are debated. Strong coupling between lattice, charge, orbital and spin degrees of freedom results in simultaneous ordering of multiple parameters, masking the mechanism that drives the transition. Here we demonstrate that the orbital domains in a manganite can be oriented by the polarization of a pulsed THz light field. Through the application of a Hubbard model, we show that domain control can be achieved by enhancing the local Coulomb interactions, which drive domain reorientation. Our results highlight the key role played by the Coulomb interaction in the control and manipulation of orbital order in the manganites and demonstrate a new way to use THz to understand and manipulate anisotropic phases in a potentially broad range of correlated materials. Numerous correlated materials exhibit an in-plane anisotropic ground state but their origin is unclear. Here the authors control the orientation of orbital domains in a manganite using the polarization of terahertz pulses, which can be explained by field-induced enhancement of the electron interactions.
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20
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Radaelli PG, Dhesi SS. The contribution of Diamond Light Source to the study of strongly correlated electron systems and complex magnetic structures. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2015; 373:rsta.2013.0148. [PMID: 25624510 DOI: 10.1098/rsta.2013.0148] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
We review some of the significant contributions to the field of strongly correlated materials and complex magnets, arising from experiments performed at the Diamond Light Source (Harwell Science and Innovation Campus, Didcot, UK) during the first few years of operation (2007-2014). We provide a comprehensive overview of Diamond research on topological insulators, multiferroics, complex oxides and magnetic nanostructures. Several experiments on ultrafast dynamics, magnetic imaging, photoemission electron microscopy, soft X-ray holography and resonant magnetic hard and soft X-ray scattering are described.
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Affiliation(s)
- P G Radaelli
- Clarendon Laboratory, Department of Physics, University of Oxford, Oxford OX1 3PU, UK
| | - S S Dhesi
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, UK
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21
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Först M, Mankowsky R, Cavalleri A. Mode-selective control of the crystal lattice. Acc Chem Res 2015; 48:380-7. [PMID: 25594102 DOI: 10.1021/ar500391x] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
CONSPECTUS: Driving phase changes by selective optical excitation of specific vibrational modes in molecular and condensed phase systems has long been a grand goal for laser science. However, phase control has to date primarily been achieved by using coherent light fields generated by femtosecond pulsed lasers at near-infrared or visible wavelengths. This field is now being advanced by progress in generating intense femtosecond pulses in the mid-infrared, which can be tuned into resonance with infrared-active crystal lattice modes of a solid. Selective vibrational excitation is particularly interesting in complex oxides with strong electronic correlations, where even subtle modulations of the crystallographic structure can lead to colossal changes of the electronic and magnetic properties. In this Account, we summarize recent efforts to control the collective phase state in solids through mode-selective lattice excitation. The key aspect of the underlying physics is the nonlinear coupling of the resonantly driven phonon to other (Raman-active) modes due to lattice anharmonicities, theoretically discussed as ionic Raman scattering in the 1970s. Such nonlinear phononic excitation leads to rectification of a directly excited infrared-active mode and to a net displacement of the crystal along the coordinate of all anharmonically coupled modes. We present the theoretical basis and the experimental demonstration of this phenomenon, using femtosecond optical spectroscopy and ultrafast X-ray diffraction at a free electron laser. The observed nonlinear lattice dynamics is shown to drive electronic and magnetic phase transitions in many complex oxides, including insulator-metal transitions, charge/orbital order melting and magnetic switching in manganites. Furthermore, we show that the selective vibrational excitation can drive high-TC cuprates into a transient structure with enhanced superconductivity. The combination of nonlinear phononics with ultrafast crystallography at X-ray free electron lasers may provide new design rules for the development of materials that exhibit these exotic behaviors also at equilibrium.
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Affiliation(s)
- M. Först
- Max-Planck Institute for the Structure and Dynamics of Matter, Hamburg 22761, Germany
- Center for Free Electron Laser Science, Hamburg 22761, Germany
| | - R. Mankowsky
- Max-Planck Institute for the Structure and Dynamics of Matter, Hamburg 22761, Germany
- Center for Free Electron Laser Science, Hamburg 22761, Germany
| | - A. Cavalleri
- Max-Planck Institute for the Structure and Dynamics of Matter, Hamburg 22761, Germany
- Center for Free Electron Laser Science, Hamburg 22761, Germany
- Department of Physics, Oxford University, Clarendon Laboratory, Oxford OX1 3PU, U.K
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22
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De Sarkar S, Sensarma R, Sengupta K. A perturbative renormalization group approach to driven quantum systems. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:325602. [PMID: 25054233 DOI: 10.1088/0953-8984/26/32/325602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We use a perturbative momentum shell renormalization group (RG) approach to study the properties of a driven quantum system at zero temperature. To illustrate the technique, we consider a bosonic ϕ(4) theory with an arbitrary time dependent interaction parameter λ(t) = λ f(ω0t), where ω0 is the drive frequency and we derive the RG equations for the system using a Keldysh diagrammatic technique. We show that the scaling of ω0 is analogous to that of temperature for a system in thermal equilibrium and its presence provides a cutoff scale for the RG flow. We analyze the resultant RG equations, derive an analytical condition for such a drive to take the system out of the gaussian regime, and show that the onset of the non-gaussian regime occurs concomitantly with the appearance of non-perturbative mode coupling terms in the effective action of the system. We supplement the above-mentioned results by obtaining them from equations of motion of the bosons and discuss their significance for systems near critical points described by time-dependent Landau-Ginzburg theories.
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Affiliation(s)
- Sangita De Sarkar
- Theoretical Physics Department, Indian Association for the Cultivation of Science, Kolkata 700032, India
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23
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Zhou SY, Langner MC, Zhu Y, Chuang YD, Rini M, Glover TE, Hertlein MP, Gonzalez AGC, Tahir N, Tomioka Y, Tokura Y, Hussain Z, Schoenlein RW. Glass-like recovery of antiferromagnetic spin ordering in a photo-excited manganite Pr₀.₇Ca₀.₃MnO₃. Sci Rep 2014; 4:4050. [PMID: 24522173 PMCID: PMC3923209 DOI: 10.1038/srep04050] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 01/16/2014] [Indexed: 11/09/2022] Open
Abstract
Electronic orderings of charges, orbitals and spins are observed in many strongly correlated electron materials, and revealing their dynamics is a critical step toward undertsanding the underlying physics of important emergent phenomena. Here we use time-resolved resonant soft x-ray scattering spectroscopy to probe the dynamics of antiferromagnetic spin ordering in the manganite Pr₀.₇Ca₀.₃MnO₃ following ultrafast photo-exitation. Our studies reveal a glass-like recovery of the spin ordering and a crossover in the dimensionality of the restoring interaction from quasi-1D at low pump fluence to 3D at high pump fluence. This behavior arises from the metastable state created by photo-excitation, a state characterized by spin disordered metallic droplets within the larger charge- and spin-ordered insulating domains. Comparison with time-resolved resistivity measurements suggests that the collapse of spin ordering is correlated with the insulator-to-metal transition, but the recovery of the insulating phase does not depend on the re-establishment of the spin ordering.
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Affiliation(s)
- S Y Zhou
- 1] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA [2] State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics, Tsinghua University, Beijing 100084, China [3] Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - M C Langner
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Y Zhu
- 1] Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA [2] Department of Applied Science, University of California, Davis, CA 95616, USA
| | - Y-D Chuang
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - M Rini
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - T E Glover
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - M P Hertlein
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - A G Cruz Gonzalez
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - N Tahir
- 1] Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA [2] National Center for Physics, Islamabad, Pakistan
| | - Y Tomioka
- Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Tsukuba Central 4, 1-1-1 Higashi Tsukuba 305-8562, Japan
| | - Y Tokura
- 1] Department of Applied Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan [2] Cross-Correlated Materials Research Group (CMRG) and Correlated Electron Research Group (CERG), Advanced Science Institute, RIKEN, Wako 351-0198, Japan
| | - Z Hussain
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - R W Schoenlein
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
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24
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Piazza L, Ma C, Yang HX, Mann A, Zhu Y, Li JQ, Carbone F. Ultrafast structural and electronic dynamics of the metallic phase in a layered manganite. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2014; 1:014501. [PMID: 26913564 PMCID: PMC4711593 DOI: 10.1063/1.4835116] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Accepted: 10/31/2013] [Indexed: 05/06/2023]
Abstract
The transition between different states in manganites can be driven by various external stimuli. Controlling these transitions with light opens the possibility to investigate the microscopic path through which they evolve. We performed femtosecond (fs) transmission electron microscopy on a bi-layered manganite to study its response to ultrafast photoexcitation. We show that a photoinduced temperature jump launches a pressure wave that provokes coherent oscillations of the lattice parameters, detected via ultrafast electron diffraction. Their impact on the electronic structure are monitored via ultrafast electron energy loss spectroscopy, revealing the dynamics of the different orbitals in response to specific structural distortions.
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Affiliation(s)
- L Piazza
- Laboratory for Ultrafast Microscopy and Electron Scattering , ICMP, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - C Ma
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics , Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - H X Yang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics , Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - A Mann
- Laboratory for Ultrafast Microscopy and Electron Scattering , ICMP, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Y Zhu
- Department of Condensed Matter Physics, Brookhaven National Laboratory , Upton, New York 11973, USA
| | - J Q Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics , Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - F Carbone
- Laboratory for Ultrafast Microscopy and Electron Scattering , ICMP, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
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25
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Moritz B, Kemper AF, Sentef M, Devereaux TP, Freericks JK. Electron-mediated relaxation following ultrafast pumping of strongly correlated materials: model evidence of a correlation-tuned crossover between thermal and nonthermal states. PHYSICAL REVIEW LETTERS 2013; 111:077401. [PMID: 23992080 DOI: 10.1103/physrevlett.111.077401] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Indexed: 06/02/2023]
Abstract
We examine electron-electron mediated relaxation following ultrafast electric field pump excitation of the fermionic degrees of freedom in the Falicov-Kimball model for correlated electrons. The results reveal a dichotomy in the temporal evolution of the system as one tunes through the Mott metal-to-insulator transition: in the metallic regime relaxation can be characterized by evolution toward a steady state well described by Fermi-Dirac statistics with an increased effective temperature; however, in the insulating regime this quasithermal paradigm breaks down with relaxation toward a nonthermal state with a complicated electronic distribution as a function of momentum. We characterize the behavior by studying changes in the energy, photoemission response, and electronic distribution as functions of time. This relaxation may be observable qualitatively on short enough time scales that the electrons behave like an isolated system not in contact with additional degrees of freedom which would act as a thermal bath, especially when using strong driving fields and studying materials whose physics may manifest the effects of correlations.
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Affiliation(s)
- B Moritz
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
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26
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Fink J, Schierle E, Weschke E, Geck J. Resonant elastic soft x-ray scattering. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2013; 76:056502. [PMID: 23563216 DOI: 10.1088/0034-4885/76/5/056502] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Resonant (elastic) soft x-ray scattering (RSXS) offers a unique element, site and valence specific probe to study spatial modulations of charge, spin and orbital degrees of freedom in solids on the nanoscopic length scale. It is not only used to investigate single-crystalline materials. This method also enables one to examine electronic ordering phenomena in thin films and to zoom into electronic properties emerging at buried interfaces in artificial heterostructures. During the last 20 years, this technique, which combines x-ray scattering with x-ray absorption spectroscopy, has developed into a powerful probe to study electronic ordering phenomena in complex materials and furthermore delivers important information on the electronic structure of condensed matter. This review provides an introduction to the technique, covers the progress in experimental equipment, and gives a survey on recent RSXS studies of ordering in correlated electron systems and at interfaces.
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Affiliation(s)
- J Fink
- Leibniz-Institute for Solid State and Materials Research Dresden, PO Box 270116, D-01171 Dresden, Germany.
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Li T, Patz A, Mouchliadis L, Yan J, Lograsso TA, Perakis IE, Wang J. Femtosecond switching of magnetism via strongly correlated spin-charge quantum excitations. Nature 2013; 496:69-73. [PMID: 23552945 DOI: 10.1038/nature11934] [Citation(s) in RCA: 135] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2012] [Accepted: 01/21/2013] [Indexed: 11/09/2022]
Abstract
The technological demand to push the gigahertz (10(9) hertz) switching speed limit of today's magnetic memory and logic devices into the terahertz (10(12) hertz) regime underlies the entire field of spin-electronics and integrated multi-functional devices. This challenge is met by all-optical magnetic switching based on coherent spin manipulation. By analogy to femtosecond chemistry and photosynthetic dynamics--in which photoproducts of chemical and biochemical reactions can be influenced by creating suitable superpositions of molecular states--femtosecond-laser-excited coherence between electronic states can switch magnetic order by 'suddenly' breaking the delicate balance between competing phases of correlated materials: for example, manganites exhibiting colossal magneto-resistance suitable for applications. Here we show femtosecond (10(-15) seconds) photo-induced switching from antiferromagnetic to ferromagnetic ordering in Pr0.7Ca0.3MnO3, by observing the establishment (within about 120 femtoseconds) of a huge temperature-dependent magnetization with photo-excitation threshold behaviour absent in the optical reflectivity. The development of ferromagnetic correlations during the femtosecond laser pulse reveals an initial quantum coherent regime of magnetism, distinguished from the picosecond (10(-12) seconds) lattice-heating regime characterized by phase separation without threshold behaviour. Our simulations reproduce the nonlinear femtosecond spin generation and underpin fast quantum spin-flip fluctuations correlated with coherent superpositions of electronic states to initiate local ferromagnetic correlations. These results merge two fields, femtosecond magnetism in metals and band insulators, and non-equilibrium phase transitions of strongly correlated electrons, in which local interactions exceeding the kinetic energy produce a complex balance of competing orders.
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Affiliation(s)
- Tianqi Li
- Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA
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