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Song XJ, Xiong YA, Zhou RJ, Cao XX, Jing ZY, Ji HR, Gu ZX, Sha TT, Xiong RG, You YM. The First Demonstration of Strain-Controlled Periodic Ferroelectric Domains with Superior Piezoelectric Response in Molecular Materials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2211584. [PMID: 36840984 DOI: 10.1002/adma.202211584] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 02/03/2023] [Indexed: 05/12/2023]
Abstract
Achieving a periodic domain structure in ferroelectric materials to tailor the macroscopic properties or realize new functions has always been a hot topic. However, methods to construct periodic domain structures, such as epitaxial growth, direct writing by scanning tips, and the patterned electrode method, are difficult or inefficient to implement in emerging molecular ferroelectrics, which have the advantages of lightweight, flexibility, biocompatibility, etc. An efficient method for constructing and controlling periodic domain structures is urgently needed to facilitate the development of molecular ferroelectrics in nanoelectronic devices. In this work, it is demonstrated that large-area, periodic and controllable needle-like domain structures can be achieved in thin films of the molecular ferroelectric trimethylchloromethyl ammonium trichlorocadmium (TMCM-CdCl3 ) upon the application of tensile strain. The domain evolution under various tensile strains can be clearly observed, and such processes are accordingly identified. Furthermore, the domain wall exhibits a superior piezoelectric response, with up to fivefold enhancement compared to that of the pristine samples. Such large-area tunable periodic domain structure and abnormally strong piezoresponse are not only of great interests in fundamental studies, but also highly important in the future applications in functional molecular materials.
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Affiliation(s)
- Xian-Jiang Song
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
- Ordered Matter Science Research Center, Nanchang University, Nanchang, 330031, P. R. China
| | - Yu-An Xiong
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
| | - Ru-Jie Zhou
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
| | - Xiao-Xing Cao
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
| | - Zheng-Yin Jing
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
| | - Hao-Ran Ji
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
| | - Zhu-Xiao Gu
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
| | - Tai-Ting Sha
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
| | - Ren-Gen Xiong
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
- Ordered Matter Science Research Center, Nanchang University, Nanchang, 330031, P. R. China
| | - Yu-Meng You
- Jiangsu Key Laboratory for Science and Applications of Molecular Ferroelectrics, Southeast University, Nanjing, 211189, P. R. China
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2
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Li L, Huang F, Shi Y, Luo ZZ, Wang GQ, Li XX, Li B, Zhang L, Yu Y, Feng YN, Yang C, Yu Y, Poeppelmeier KR. Triple-Wavelength Lasing with a Stabilized β-LaBSiO 5:Nd 3+ Crystal. J Am Chem Soc 2022; 144:11822-11830. [PMID: 35679487 DOI: 10.1021/jacs.2c04331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Multi-wavelength lasers, especially the triple-wavelength laser around 1060 nm, could be produced by the 4F3/2 → 4I11/2 transition of Nd3+ and present numerous challenges and opportunities in the field of optoelectronics. The Nd3+-doped high-temperature phase of LaBSiO5 (β-LBSO) is an ideal crystal to produce triple-wavelength lasers; however, the crystal growth is challenging because of the phase transition from β-LBSO to low-temperature phase (α-LBSO) at 162 °C. This phase transition is successfully suppressed when the doping content of Nd3+ is larger than 6.3 at. %, and the Nd3+-doped β-LBSO is stable at room temperature. The local disorder of BO4 tetrahedra due to Nd3+ doping is essential to the stabilization of β-LBSO. For the first time, the β-LBSO:8%Nd3+ crystal with a dimension of 1.8 × 1.8 × 1.8 cm3 is obtained through the top-seeded solution method. The crystal shows strong optical absorption in the range of 785-815 nm, matching well with the commercial laser diode pumping source. The optical emission of 4F3/2 → 4I11/2 splits into four peaks with the highest optical emission cross section of 2.14 × 10-20 cm2 at 1068 nm. The continuous-wave triple-wavelength generation of coherent light at 1047, 1071, and 1092 nm is achieved with the highest output power of 235 mW and efficiency of 12.1%.
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Affiliation(s)
- Lingyun Li
- Key Laboratory of Advanced Materials Technologies, College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P. R. China
| | - Fazheng Huang
- Key Laboratory of Advanced Materials Technologies, College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P. R. China
| | - Yi Shi
- Key Laboratory of Advanced Materials Technologies, College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P. R. China
| | - Zhong-Zhen Luo
- Key Laboratory of Advanced Materials Technologies, College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P. R. China
| | - Guo-Qiang Wang
- Key Laboratory of Advanced Materials Technologies, College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P. R. China
| | - Xin-Xiong Li
- College of Chemistry, Fuzhou University, Fuzhou 350108, P. R. China
| | - Bingxuan Li
- Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, P. R. China
| | - Lizhen Zhang
- Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, P. R. China
| | - Yi Yu
- Research Center for Rare Earth Materials and Applications, School of Physics and Electronic Information, Gannan Normal University, Ganzhou 341000, P. R. China
| | - Ya-Nan Feng
- Key Laboratory of Advanced Materials Technologies, College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P. R. China
| | - Chengkai Yang
- Key Laboratory of Advanced Materials Technologies, College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P. R. China
| | - Yan Yu
- Key Laboratory of Advanced Materials Technologies, College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, P. R. China
| | - Kenneth R Poeppelmeier
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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3
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Ghasemian MB, Daeneke T, Shahrbabaki Z, Yang J, Kalantar-Zadeh K. Peculiar piezoelectricity of atomically thin planar structures. NANOSCALE 2020; 12:2875-2901. [PMID: 31984979 DOI: 10.1039/c9nr08063e] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The emergence of piezoelectricity in two-dimensional (2D) materials has represented a milestone towards employing low-dimensional structures for future technologies. 2D piezoelectric materials possess unique and unprecedented characteristics that cannot be found in other morphologies; therefore, the applications of piezoelectricity can be substantially extended. By reducing the thickness into the 2D realm, piezoelectricity might be induced in otherwise non-piezoelectric materials. The origin of the enhanced piezoelectricity in such thin planes is attributed to the loss of centrosymmetry, altered carrier concentration, and change in local polarization and can be efficiently tailored via surface modifications. Access to such materials is important from a fundamental research point of view, to observe the extraordinary interactions between free charge carriers, phonons and photons, and also with respect to device development, for which planar structures provide the required compatibility with the large-scale fabrication technologies of integrated circuits. The existence of piezoelectricity in 2D materials presents great opportunities for applications in various fields of electronics, optoelectronics, energy harvesting, sensors, actuators and biotechnology. Additionally, 2D flexible nanostructures with superior piezoelectric properties are distinctive candidates for integration into nano-scale electromechanical systems. Here we fundamentally review the state of the art of 2D piezoelectric materials from both experimental and theoretical aspects and report the recent achievements in the synthesis, characterization and applications of these materials.
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Affiliation(s)
- Mohammad B Ghasemian
- School of Chemical Engineering, University of New South Wales (UNSW), Sydney Campus, NSW 2052, Australia.
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4
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Yin L, Mi W. Progress in BiFeO 3-based heterostructures: materials, properties and applications. NANOSCALE 2020; 12:477-523. [PMID: 31850428 DOI: 10.1039/c9nr08800h] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
BiFeO3-based heterostructures have attracted much attention for potential applications due to their room-temperature multiferroic properties, proper band gaps and ultrahigh ferroelectric polarization of BiFeO3, such as data storage, optical utilization in visible light regions and synapse-like function. Here, this work aims to offer a systematic review on the progress of BiFeO3-based heterostructures. In the first part, the optical, electric, magnetic, and valley properties and their interactions in BiFeO3-based heterostructures are briefly reviewed. In the second part, the morphologies of BiFeO3 and medium materials in the heterostructures are discussed. Particularly, in the third part, the physical properties and underlying mechanism in BiFeO3-based heterostructures are discussed thoroughly, such as the photovoltaic effect, electric field control of magnetism, resistance switching, and two-dimensional electron gas and valley characteristics. The fourth part illustrates the applications of BiFeO3-based heterostructures based on the materials and physical properties discussed in the second and third parts. This review also includes a future prospect, which can provide guidance for exploring novel physical properties and designing multifunctional devices.
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Affiliation(s)
- Li Yin
- Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, School of Science, Tianjin University, Tianjin 300354, China.
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Ahn Y, Pateras A, Marks SD, Xu H, Zhou T, Luo Z, Chen Z, Chen L, Zhang X, DiChiara AD, Wen H, Evans PG. Nanosecond Optically Induced Phase Transformation in Compressively Strained BiFeO_{3} on LaAlO_{3}. PHYSICAL REVIEW LETTERS 2019; 123:045703. [PMID: 31491252 DOI: 10.1103/physrevlett.123.045703] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Revised: 05/08/2019] [Indexed: 06/10/2023]
Abstract
Above-band-gap optical illumination of compressively strained BiFeO_{3} induces a transient reversible transformation from a state of coexisting tilted tetragonal-like and rhombohedral-like phases to an untilted tetragonal-like phase. Time-resolved synchrotron x-ray diffraction reveals that the transformation is induced by an ultrafast optically induced lattice expansion that shifts the relative free energies of the tetragonal-like and rhombohedral-like phases. The transformation proceeds at interfaces between regions of the tetragonal-like phase and regions of a mixture of tilted phases, consistent with the motion of a phase boundary. The optically induced transformation demonstrates that there are new optically driven routes towards nanosecond-scale control of phase transformations in ferroelectrics and multiferroics.
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Affiliation(s)
- Youngjun Ahn
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Anastasios Pateras
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Samuel D Marks
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
| | - Han Xu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Tao Zhou
- ID01/ESRF, 71 Avenue des Martyrs, 38000 Grenoble Cedex, France
| | - Zhenlin Luo
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zuhuang Chen
- School of Materials Science and Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Lang Chen
- Department of Physics, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China
| | - Xiaoyi Zhang
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Anthony D DiChiara
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Haidan Wen
- Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Paul G Evans
- Department of Materials Science and Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA
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6
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Liou YD, Chiu YY, Hart RT, Kuo CY, Huang YL, Wu YC, Chopdekar RV, Liu HJ, Tanaka A, Chen CT, Chang CF, Tjeng LH, Cao Y, Nagarajan V, Chu YH, Chen YC, Yang JC. Deterministic optical control of room temperature multiferroicity in BiFeO 3 thin films. NATURE MATERIALS 2019; 18:580-587. [PMID: 31061484 DOI: 10.1038/s41563-019-0348-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 03/15/2019] [Indexed: 05/12/2023]
Abstract
Controlling ferroic orders (ferroelectricity, ferromagnetism and ferroelasticity) by optical methods is a significant challenge due to the large mismatch in energy scales between the order parameter coupling strengths and the incident photons. Here, we demonstrate an approach to manipulate multiple ferroic orders in an epitaxial mixed-phase BiFeO3 thin film at ambient temperature via laser illumination. Phase-field simulations indicate that a light-driven flexoelectric effect allows the targeted formation of ordered domains. We also achieved precise sequential laser writing and erasure of different domain patterns, which demonstrates a deterministic optical control of multiferroicity at room temperature. As ferroic orders directly influence susceptibility and conductivity in complex materials, our results not only shed light on the optical control of multiple functionalities, but also suggest possible developments for optoelectronics and related applications.
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Affiliation(s)
- Yi-De Liou
- Department of Physics, National Cheng Kung University, Tainan, Taiwan
| | - Yu-You Chiu
- Department of Physics, National Cheng Kung University, Tainan, Taiwan
| | - Ryan Thomas Hart
- Department of Materials Science and Engineering, University of Texas at Arlington, Arlington, TX, USA
| | - Chang-Yang Kuo
- Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany
- National Synchrotron Radiation Research Center, Hsinchu, Taiwan
| | - Yen-Lin Huang
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan
| | - Yuan-Chih Wu
- Department of Physics, National Cheng Kung University, Tainan, Taiwan
| | - Rajesh V Chopdekar
- Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Heng-Jui Liu
- Department of Materials Science and Engineering, National Chung Hsing University, Taichung, Taiwan
| | - Arata Tanaka
- Department of Quantum Matter, ADSM, Hiroshima University, Higashi-Hiroshima, Japan
| | - Chien-Te Chen
- National Synchrotron Radiation Research Center, Hsinchu, Taiwan
| | - Chun-Fu Chang
- Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - Liu Hao Tjeng
- Max-Planck Institute for Chemical Physics of Solids, Dresden, Germany
| | - Ye Cao
- Department of Materials Science and Engineering, University of Texas at Arlington, Arlington, TX, USA
| | - Valanoor Nagarajan
- School of Materials Science and Engineering, University of New South Wales, Sydney, New South Wales, Australia
| | - Ying-Hao Chu
- Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu, Taiwan
- Center for Emergent Functional Matter Science, National Chiao Tung University, Hsinchu, Taiwan
- Institute of Physics, Academia Sinica, Taipei, Taiwan
| | - Yi-Chun Chen
- Department of Physics, National Cheng Kung University, Tainan, Taiwan.
- Center for Quantum Frontiers of Research & Technology (QFort), National Cheng Kung University, Tainan, Taiwan.
| | - Jan-Chi Yang
- Department of Physics, National Cheng Kung University, Tainan, Taiwan.
- Center for Quantum Frontiers of Research & Technology (QFort), National Cheng Kung University, Tainan, Taiwan.
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7
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Chen C, Wang C, Cai X, Xu C, Li C, Zhou J, Luo Z, Fan Z, Qin M, Zeng M, Lu X, Gao X, Kentsch U, Yang P, Zhou G, Wang N, Zhu Y, Zhou S, Chen D, Liu JM. Controllable defect driven symmetry change and domain structure evolution in BiFeO 3 with enhanced tetragonality. NANOSCALE 2019; 11:8110-8118. [PMID: 30984948 DOI: 10.1039/c9nr00932a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Defect engineering has been a powerful tool to enable the creation of exotic phases and the discovery of intriguing phenomena in ferroelectric oxides. However, the accurate control of the concentration of defects remains a big challenge. In this work, ion implantation, which can provide controllable point defects, allows us to produce a controlled defect driven true super-tetragonal (T) phase with a single-domain-state in ferroelectric BiFeO3 thin films. This point-defect engineering is found to drive the phase transition from the as-grown mixed rhombohedral-like (R) and tetragonal-like (MC) phase to true tetragonal (T) symmetry and induce the stripe multi-nanodomains to a single domain state. By further increasing the injected dose of the He ion, we demonstrate an enhanced tetragonality super-tetragonal (super-T) phase with the largest c/a ratio of ∼1.3 that has ever been experimentally achieved in BiFeO3. A combination of the morphology change and domain evolution further confirms that the mixed R/MC phase structure transforms to the single-domain-state true tetragonal phase. Moreover, the re-emergence of the R phase and in-plane nanoscale multi-domains after heat treatment reveal the memory effect and reversible phase transition and domain evolution. Our findings demonstrate the reversible control of R-Mc-T-super T symmetry changes (leading to the creation of true T phase BiFeO3 with enhanced tetragonality) and multidomain-single domain structure evolution through controllable defect engineering. This work also provides a pathway to generate large tetragonality (or c/a ratio) that could be extended to other ferroelectric material systems (such as PbTiO3, BaTiO3 and HfO2) which might lead to strong polarization enhancement.
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Affiliation(s)
- Chao Chen
- Institute for Advanced Materials, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, China.
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8
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Herklotz A, Rus SF, Balke N, Rouleau C, Guo EJ, Huon A, Kc S, Roth R, Yang X, Vaswani C, Wang J, Orth PP, Scheurer MS, Ward TZ. Designing Morphotropic Phase Composition in BiFeO 3. NANO LETTERS 2019; 19:1033-1038. [PMID: 30673240 DOI: 10.1021/acs.nanolett.8b04322] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In classical morphotropic piezoelectric materials, rhombohedral and tetragonal phase variants can energetically compete to form a mixed phase regime with improved functional properties. While the discovery of morphotropic-like phases in multiferroic BiFeO3 films has broadened this definition, accessing these phase spaces is still typically accomplished through isovalent substitution or heteroepitaxial strain which do not allow for continuous modification of phase composition postsynthesis. Here, we show that it is possible to use low-energy helium implantation to tailor morphotropic phases of epitaxial BiFeO3 films postsynthesis in a continuous and iterative manner. Applying this strain doping approach to morphotropic films creates a new phase space based on internal and external lattice stress that can be seen as an analogue to temperature-composition phase diagrams of classical morphotropic ferroelectric systems.
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Affiliation(s)
- Andreas Herklotz
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
- Institute of Physics , Martin Luther University of Halle-Wittenberg , Halle 06099 , Germany
| | - Stefania F Rus
- Renewable Energies - Photovoltaics Laboratory , National Institute for Research and Development in Electrochemistry and Condensed Matter , Timisoara 300569 , Romania
| | - Nina Balke
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Christopher Rouleau
- Center for Nanophase Materials Sciences , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Er-Jia Guo
- Neutron Scattering Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Amanda Huon
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
- Department of Materials Science and Engineering , Drexel University , Philadelphia , Pennsylvania 19104 , United States
| | - Santosh Kc
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
| | - Robert Roth
- Institute of Physics , Martin Luther University of Halle-Wittenberg , Halle 06099 , Germany
| | - Xu Yang
- Department of Physics and Astronomy and Ames Laboratory-U.S. DOE , Iowa State University , Ames , Iowa 50011 , United States
| | - Chirag Vaswani
- Department of Physics and Astronomy and Ames Laboratory-U.S. DOE , Iowa State University , Ames , Iowa 50011 , United States
| | - Jigang Wang
- Department of Physics and Astronomy and Ames Laboratory-U.S. DOE , Iowa State University , Ames , Iowa 50011 , United States
| | - Peter P Orth
- Department of Physics and Astronomy and Ames Laboratory-U.S. DOE , Iowa State University , Ames , Iowa 50011 , United States
| | - Mathias S Scheurer
- Department of Physics , Harvard University , Cambridge , Massachusetts 02138 , United States
| | - Thomas Z Ward
- Materials Science and Technology Division , Oak Ridge National Laboratory , Oak Ridge , Tennessee 37831 , United States
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9
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Chu K, Yang CH. High-resolution angle-resolved lateral piezoresponse force microscopy: Visualization of in-plane piezoresponse vectors. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:123704. [PMID: 30599567 DOI: 10.1063/1.5052662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 11/12/2018] [Indexed: 06/09/2023]
Abstract
Piezoresponse force microscopy (PFM) is a widely used tool for ferroelectric domain imaging. Lateral PFM (LPFM) utilizes the torsional vibration mode of a probe cantilever; it can distinguish ferroelectric domains having different polarizations with respect to the axis perpendicular to the cantilever, but it is blind to the parallel axis innately. We introduce a high-resolution angle-resolved-LPFM technique that is capable of visualizing full two-dimensional in-plane piezoresponse vector fields. The LPFM signal is analyzed for each pixel with respect to the sample-probe orientation angle with the aid of an image registration technique, and the corresponding local in-plane piezoresponse vector is deduced from the amplitude and phase of the trigonometric curve fitting. This technique provides a pathway for the visualization of complicated ferroelectric and piezoelectric structures.
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Affiliation(s)
- Kanghyun Chu
- Department of Physics, KAIST, Daejeon 34141, South Korea
| | - Chan-Ho Yang
- Department of Physics, KAIST, Daejeon 34141, South Korea
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10
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Sharma P, Kang KR, Liu YY, Jang BK, Li JY, Yang CH, Seidel J. Optimizing the electromechanical response in morphotropic BiFeO 3. NANOTECHNOLOGY 2018; 29:205703. [PMID: 29480164 DOI: 10.1088/1361-6528/aab226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Affiliation(s)
- P Sharma
- School of Materials Science and Engineering, UNSW Australia, Sydney NSW 2052, Australia
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11
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Kim B, Barrows FP, Sharma Y, Katiyar RS, Phatak C, Petford-Long AK, Jeon S, Hong S. Ferroelectric Domain Studies of Patterned (001) BiFeO 3 by Angle-Resolved Piezoresponse Force Microscopy. Sci Rep 2018; 8:203. [PMID: 29317737 PMCID: PMC5760526 DOI: 10.1038/s41598-017-18482-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 12/07/2017] [Indexed: 11/12/2022] Open
Abstract
We have studied the ferroelectric domains in (001) BiFeO3 (BFO) films patterned into mesas with various aspect ratios, using angle-resolved piezoresponse force microscope (AR-PFM), which can image the in-plane polarization component with an angular resolution of 30°. We observed not only stable polarization variants, but also meta-stable polarization variants, which can reduce the charge accumulated at domain boundaries. We considered the number of neighboring domains that are in contact, in order to analyze the complexity of the ferroelectric domain structure. Comparison of the ferroelectric domains from the patterned and unpatterned regions showed that the elastic relaxation induced by removal of the film surrounding the mesas led to a reduction of the average number of neighboring domains, indicative of a decrease in domain complexity. We also found that the rectangular BFO patterns with high aspect ratio had a simpler domain configuration and enhanced piezoelectric characteristics than square-shaped mesas. Manipulation of the ferroelectric domains by controlling the aspect ratio of the patterned BFO thin film mesas can be useful for nanoelectronic applications.
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Affiliation(s)
- Bumsoo Kim
- Department of Materials Science and Engineering, KAIST, Daejeon, 305-701, Korea
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Frank P Barrows
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
- Applied Physics Program, Northwestern University, Evanston, IL, 60208, USA
| | - Yogesh Sharma
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
- Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, PR-00936-8377, USA
| | - Ram S Katiyar
- Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, San Juan, PR-00936-8377, USA
| | - Charudatta Phatak
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
| | - Amanda K Petford-Long
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA
- Materials Science and Engineering Department, Northwestern University, Evanston, IL, 60208, USA
| | - Seokwoo Jeon
- Department of Materials Science and Engineering, KAIST, Daejeon, 305-701, Korea.
| | - Seungbum Hong
- Department of Materials Science and Engineering, KAIST, Daejeon, 305-701, Korea.
- Materials Science Division, Argonne National Laboratory, Lemont, IL, 60439, USA.
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12
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Heo Y, Hu S, Sharma P, Kim KE, Jang BK, Cazorla C, Yang CH, Seidel J. Impact of Isovalent and Aliovalent Doping on Mechanical Properties of Mixed Phase BiFeO 3. ACS NANO 2017; 11:2805-2813. [PMID: 28225589 DOI: 10.1021/acsnano.6b07869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
In this study, we report the effect of doping in morphotropic BiFeO3 (BFO) thin films on mechanical properties, revealing variations in the elasticity across the competing phases and their boundaries. Spectroscopic force-distance (F-D) curves and force mapping images by AFM are used to characterize the structure and elastic properties of three BFO thin-film candidates (pure-BFO, Ca-doped BFO, La-doped BFO). We show that softening behavior is observed in isovalent La-doped BFO, whereas hardening is seen in aliovalent Ca-doped BFO. Furthermore, quantitative F-D measurements are extended to show threshold strengths for phase transitions, revealing their dependence on doping in the system. First-principles simulation methods are also employed to understand the observed mechanical properties in pure and doped BFO thin films and to provide microscopic insight on them. These results provide key insight into doping as an effective control parameter to tune nanomechanical properties and suggest an alternative framework to control coupled ferroic functionalities at the nanoscale.
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Affiliation(s)
- Yooun Heo
- School of Materials Science and Engineering and ‡Integrated Materials Design Centre, University of New South Wales (UNSW) Australia , Sydney, New South Wales 2052, Australia
- Department of Physics and ∥Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 305-701, Republic of Korea
| | - Songbai Hu
- School of Materials Science and Engineering and ‡Integrated Materials Design Centre, University of New South Wales (UNSW) Australia , Sydney, New South Wales 2052, Australia
- Department of Physics and ∥Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 305-701, Republic of Korea
| | - Pankaj Sharma
- School of Materials Science and Engineering and ‡Integrated Materials Design Centre, University of New South Wales (UNSW) Australia , Sydney, New South Wales 2052, Australia
- Department of Physics and ∥Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 305-701, Republic of Korea
| | - Kwang-Eun Kim
- School of Materials Science and Engineering and ‡Integrated Materials Design Centre, University of New South Wales (UNSW) Australia , Sydney, New South Wales 2052, Australia
- Department of Physics and ∥Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 305-701, Republic of Korea
| | - Byung-Kweon Jang
- School of Materials Science and Engineering and ‡Integrated Materials Design Centre, University of New South Wales (UNSW) Australia , Sydney, New South Wales 2052, Australia
- Department of Physics and ∥Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 305-701, Republic of Korea
| | - Claudio Cazorla
- School of Materials Science and Engineering and ‡Integrated Materials Design Centre, University of New South Wales (UNSW) Australia , Sydney, New South Wales 2052, Australia
- Department of Physics and ∥Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 305-701, Republic of Korea
| | - Chan-Ho Yang
- School of Materials Science and Engineering and ‡Integrated Materials Design Centre, University of New South Wales (UNSW) Australia , Sydney, New South Wales 2052, Australia
- Department of Physics and ∥Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 305-701, Republic of Korea
| | - Jan Seidel
- School of Materials Science and Engineering and ‡Integrated Materials Design Centre, University of New South Wales (UNSW) Australia , Sydney, New South Wales 2052, Australia
- Department of Physics and ∥Institute for the NanoCentury, Korea Advanced Institute of Science and Technology (KAIST) , Daejeon 305-701, Republic of Korea
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13
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Sharma P, Heo Y, Jang BK, Liu YY, Li JY, Yang CH, Seidel J. Structural and electronic transformation pathways in morphotropic BiFeO3. Sci Rep 2016; 6:32347. [PMID: 27581222 PMCID: PMC5007483 DOI: 10.1038/srep32347] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 08/02/2016] [Indexed: 11/20/2022] Open
Abstract
Phase boundaries in multiferroics, in which (anti-)ferromagnetic, ferroelectric and ferroelastic order parameters coexist, enable manipulation of magnetism and electronic properties by external electric fields through switching of the polarization in the material. It has been shown that the strain-driven morphotropic phase boundaries in a single-phase multiferroic such as BiFeO3 (BFO) can exhibit distinct electronic conductivity. However, the control of ferroelectric and phase switching and its correlation with phase boundary conductivity in this material has been a significant challenge. Supported by a thermodynamic approach, here we report a concept to precisely control different switching pathways and the associated control of electronic conductivity in mixed phase BFO. This work demonstrates a critical step to control and use non-volatile strain-conductivity coupling at the nanoscale. Beyond this observation, it provides a framework for exploring a route to control multiple order parameters coupled to ferroelastic and ferroelectric order in multiferroic materials.
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Affiliation(s)
- P Sharma
- School of Materials Science and Engineering, UNSW Australia, Sydney NSW 2052, Australia
| | - Y Heo
- School of Materials Science and Engineering, UNSW Australia, Sydney NSW 2052, Australia
| | - B-K Jang
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea
| | - Y Y Liu
- School of Materials Science and Engineering, Xiangtan University, Xiangtan, Hunan 411105, China
| | - J Y Li
- Department of Mechanical Engineering, University of Washington, Seattle, Washington 98195-2600, USA
| | - C-H Yang
- Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Republic of Korea.,Institute for the NanoCentury, KAIST, Daejeon 305-701, Republic of Korea
| | - J Seidel
- School of Materials Science and Engineering, UNSW Australia, Sydney NSW 2052, Australia
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14
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Li P, Dong X, Gao Y, Ren L, Jin K. Photocarrier transport and dynamics in mixed-phase BiFeO 3 films. OPTICS EXPRESS 2016; 24:9119-9129. [PMID: 27137339 DOI: 10.1364/oe.24.009119] [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 report a remarkable photoinduced relaxation process and its dependence of thickness and temperature in mixed-phase BiFeO3 films grown on (001) LaAlO3 substrates. When the films are illuminated by the light above the bandgap, their resistances are reduced with the increase of temperature. The photoinduced change of resistance reaches to the maximum of about 2.17 × 105% at 300 K. It is noted that the relaxation processes of the resistance are significantly different between T-like phase and T-R mixed phase due to structural strain, symmetry breaking and built-in electric field at the phase boundaries. These results provide more insights into intrinsic mechanisms of mixed-phase multiferroic materials and potential applications in all-oxide photoelectric devices.
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15
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Chen L, Cheng Z, Xu W, Meng X, Yuan G, Liu J, Liu Z. Electrical and mechanical switching of ferroelectric polarization in the 70 nm BiFeO3 film. Sci Rep 2016; 6:19092. [PMID: 26752105 PMCID: PMC4707501 DOI: 10.1038/srep19092] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 09/28/2015] [Indexed: 11/09/2022] Open
Abstract
Ferroelectric polarization switching and its domain evolution play a key role on the macroscopic electric properties of ferroelectric or piezoelectric devices. Mechanical switching has been reported recently in ~5 nm BaTiO3 and PbZr0.2Ti0.8O3 epitaxial films; however it is still a challenge for a mechanical force to switch polarization of a slightly thicker film in the same way as an electric field. Here, we report that the polarization of a 70 nm BiFeO3 epitaxial film can be completely switched by a mechanical force, and its domain evolution is similar to that observed with electrical switching. With the gradual increase of the field/force, new domains nucleate preferentially at domain boundaries, the μm-size domains commonly decompose to a mass of nm-size domains, and finally they may reorganize to μm-size domains which undergo 180(°) polarization switching through multi steps. Importantly, the complete mechanical switching of polarization was also established in the (0 0 1) film with a smooth surface. Furthermore, either upward or downward polarization can be read out nondestructively by a constant current. Our study sheds light on prospective applications of ferroelectrics in the absence of an electric field, such as memory devices and other micro-electromechanical systems.
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Affiliation(s)
- Liufang Chen
- School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China
| | - Zhihao Cheng
- School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China
| | - Wenting Xu
- School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China
| | - Xiangjian Meng
- National Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Yu Tian Road 500, Shanghai 200083, P. R. China
| | - Guoliang Yuan
- School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, P. R. China
| | - Junming Liu
- National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Zhiguo Liu
- National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, P. R. China
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Chu K, Jang BK, Sung JH, Shin YA, Lee ES, Song K, Lee JH, Woo CS, Kim SJ, Choi SY, Koo TY, Kim YH, Oh SH, Jo MH, Yang CH. Enhancement of the anisotropic photocurrent in ferroelectric oxides by strain gradients. NATURE NANOTECHNOLOGY 2015; 10:972-979. [PMID: 26322941 DOI: 10.1038/nnano.2015.191] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Accepted: 07/23/2015] [Indexed: 06/04/2023]
Abstract
The phase separation of multiple competing structural/ferroelectric phases has attracted particular attention owing to its excellent electromechanical properties. Little is known, however, about the strain-gradient-induced electronic phenomena at the interface of competing structural phases. Here, we investigate the polymorphic phase interface of bismuth ferrites using spatially resolved photocurrent measurements, present the observation of a large enhancement of the anisotropic interfacial photocurrent by two orders of magnitude, and discuss the possible mechanism on the basis of the flexoelectric effect. Nanoscale characterizations of the photosensitive area through position-sensitive angle-resolved piezoresponse force microscopy and electron holography techniques, in conjunction with phase field simulation, reveal that regularly ordered dipole-charged domain walls emerge. These findings offer practical implications for complex oxide optoelectronics.
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Affiliation(s)
- Kanghyun Chu
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea
| | - Byung-Kweon Jang
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea
| | - Ji Ho Sung
- Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk 790-784, Korea
- Center for Artificial Low-Dimensional Electronic Systems, Institute for Basic Science (IBS), POSTECH, Pohang, Gyeongbuk 790-784, Republic of Korea
| | - Yoon Ah Shin
- Department of Materials Science and Engineering, POSTECH, Pohang, Gyeongbuk 790-784, Republic of Korea
| | - Eui-Sup Lee
- Graduate School of Nanoscience and Technology, KAIST, Daejeon 305-701, Republic of Korea
| | - Kyung Song
- Department of Materials Science and Engineering, POSTECH, Pohang, Gyeongbuk 790-784, Republic of Korea
| | - Jin Hong Lee
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea
| | - Chang-Su Woo
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea
| | - Seung Jin Kim
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea
| | - Si-Young Choi
- Department of Materials Modeling and Characterization, Korea Institute of Materials Science, Changwon 642-831, Republic of Korea
| | - Tae Yeong Koo
- Pohang Accelerator Laboratory, POSTECH, Pohang, Gyeongbuk 790-784, Republic of Korea
| | - Yong-Hyun Kim
- Graduate School of Nanoscience and Technology, KAIST, Daejeon 305-701, Republic of Korea
| | - Sang-Ho Oh
- Department of Materials Science and Engineering, POSTECH, Pohang, Gyeongbuk 790-784, Republic of Korea
| | - Moon-Ho Jo
- Division of Advanced Materials Science, Pohang University of Science and Technology (POSTECH), Pohang, Gyeongbuk 790-784, Korea
- Center for Artificial Low-Dimensional Electronic Systems, Institute for Basic Science (IBS), POSTECH, Pohang, Gyeongbuk 790-784, Republic of Korea
- Department of Materials Science and Engineering, POSTECH, Pohang, Gyeongbuk 790-784, Republic of Korea
| | - Chan-Ho Yang
- Department of Physics, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 305-701, Republic of Korea
- KAIST Institute for the NanoCentury, Daejeon 305-701, Republic of Korea
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17
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Jin Y, Lu X, Zhang J, Kan Y, Bo H, Huang F, Xu T, Du Y, Xiao S, Zhu J. Studying the Polarization Switching in Polycrystalline BiFeO3 Films by 2D Piezoresponse Force Microscopy. Sci Rep 2015; 5:12237. [PMID: 26192555 PMCID: PMC4507449 DOI: 10.1038/srep12237] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Accepted: 06/23/2015] [Indexed: 11/20/2022] Open
Abstract
For rhombohedral multiferroelectrics, non-180° ferroelectric domain switching may induce ferroelastic and/or (anti-)ferromagnetic effect. So the determination and control of ferroelectric domain switching angles is crucial for nonvolatile information storage and exchange-coupled magnetoelectric devices. We try to study the intrinsic characters of polarization switching in BiFeO3 by introducing a special data processing method to determine the switching angle from 2D PFM (Piezoresponse Force Microscopy) images of randomly oriented samples. The response surface of BiFeO3 is first plotted using the piezoelectric tensor got from first principles calculations. Then from the normalized 2D PFM signals before and after switching, the switching angles of randomly oriented BiFeO3 grains can be determined through numerical calculations. In the polycrystalline BiFeO3 films, up to 34% of all switched area is that with original out-of-plane (OP) polarization parallel to the poling field. 71° polarization switching is more favorable, with the area percentages of 71°, 109° and 180° domain switching being about 42%, 29% and 29%, respectively. Our analysis further reveals that IP stress and charge migration have comparable effect on switching, and they are sensitive to the geometric arrangements. This work helps exploring a route to control polarization switching in BiFeO3, so as to realize desirable magnetoelectric coupling.
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Affiliation(s)
- Yaming Jin
- National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, P. R. China
| | - Xiaomei Lu
- 1] National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, P. R. China [2] Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Junting Zhang
- Department of Physics, China University of Mining and Technology, Xuzhou 221116, People's Republic of China
| | - Yi Kan
- National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, P. R. China
| | - Huifeng Bo
- College of Science, Hebei United University, Tangshan 063009, P. R. China
| | - Fengzhen Huang
- 1] National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, P. R. China [2] Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, P. R. China
| | - Tingting Xu
- National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, P. R. China
| | - Yingchao Du
- National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, P. R. China
| | - Shuyu Xiao
- National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, P. R. China
| | - Jinsong Zhu
- National Laboratory of Solid State Microstructures and Physics School, Nanjing University, Nanjing 210093, P. R. China
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18
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Kim KL, Huber JE. Mapping of ferroelectric domain structure using angle-resolved piezoresponse force microscopy. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:013705. [PMID: 25638088 DOI: 10.1063/1.4905334] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Angle-resolved piezoresponse force microscopy (AR-PFM) was used in conjunction with electron backscatter diffraction (EBSD) to study ferroelectric domain structure in polycrystalline near-morphotropic lead zirconate titanate (PZT). We introduce the details of AR-PFM including experimental method, the process to generate AR-PFM maps, and the interpretation of AR-PFM map, using domain patterns observed in bulk PZT. The spatial distortion caused by scanner creep and non-linearity in scanning probe microscopy was corrected through image registration, taking advantage of the features present in topography images. Domain structures were mapped using AR-PFM data, and the maps consistently show alternating piezoresponse axes in a lamellar pattern of non-180° domain structure. Comparison of AR-PFM and EBSD data showed a discrepancy between the direction of lateral surface displacement and the in-plane polarization direction. Additionally, using suitable domain patterns, AR-PFM enabled discrimination between the tetragonal and rhombohedral phases at the sub-grain scale.
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Affiliation(s)
- K L Kim
- Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, United Kingdom
| | - J E Huber
- Department of Engineering Science, University of Oxford, Oxford OX1 3PJ, United Kingdom
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19
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Heo Y, Jang BK, Kim SJ, Yang CH, Seidel J. Nanoscale mechanical softening of morphotropic BiFeO3. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2014; 26:7568-7572. [PMID: 25327302 DOI: 10.1002/adma.201401958] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Revised: 09/04/2014] [Indexed: 06/04/2023]
Abstract
Mechanical switching can be used to form phase-transformed areas in mixed-phase bismuth ferrite thin films, which might be exploited to yield various soft elastic areas with greatly reduced Young's modulus on the nanoscale. Due to the mechanically susceptible nature of morphotropic phase boundaries in multiferroics, combined elastic control of electronic, magnetic, and ferroelectric properties becomes possible.
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Affiliation(s)
- Yooun Heo
- School of Materials Science and Engineering, University of New South Wales, Sydney, NSW,, 2052, Australia
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20
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Vasudevan RK, Matsumoto Y, Cheng X, Imai A, Maruyama S, Xin HL, Okatan MB, Jesse S, Kalinin SV, Nagarajan V. Deterministic arbitrary switching of polarization in a ferroelectric thin film. Nat Commun 2014; 5:4971. [DOI: 10.1038/ncomms5971] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Accepted: 08/12/2014] [Indexed: 11/10/2022] Open
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Bhatnagar A, Kim YH, Hesse D, Alexe M. Persistent photoconductivity in strained epitaxial BiFeO3 thin films. NANO LETTERS 2014; 14:5224-8. [PMID: 25157996 DOI: 10.1021/nl502183j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A drastic change in the conductivity of strained BiFeO3 (BFO) films is observed after illuminating them with above-band gap light. This has been termed as persistent photoconductivity. The enhanced conductivity decays exponentially with time. A trapping character of the sub-band levels and their subsequent gradual emptying is proposed as a possible mechanism.
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Affiliation(s)
- Akash Bhatnagar
- Max Planck Institute of Microstructure Physics , Weinberg 2, 06120 Halle, Germany
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22
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Effects of Interfaces on the Structure and Novel Physical Properties in Epitaxial Multiferroic BiFeO₃ Ultrathin Films. MATERIALS 2014; 7:5403-5426. [PMID: 28788135 PMCID: PMC5455811 DOI: 10.3390/ma7075403] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 06/29/2014] [Accepted: 07/04/2014] [Indexed: 11/21/2022]
Abstract
In functional oxide films, different electrical/mechanical boundaries near film surfaces induce rich phase diagrams and exotic phenomena. In this paper, we review some key points which underpin structure, phase transition and related properties in BiFeO3 ultrathin films. Compared with the bulk counterparts, we survey the recent results of epitaxial BiFeO3 ultrathin films to illustrate how the atomic structure and phase are markedly influenced by the interface between the film and the substrate, and to emphasize the roles of misfit strain and depolarization field on determining the domain patterns, phase transformation and associated physical properties of BiFeO3 ultrathin films, such as polarization, piezoelectricity, and magnetism. One of the obvious consequences of the misfit strain on BiFeO3 ultrathin films is the emergence of a sequence of phase transition from tetragonal to mixed tetragonal & rhombohedral, the rhombohedral, mixed rhombohedral & orthorhombic, and finally orthorhombic phases. Other striking features of this system are the stable domain patterns and the crossover of 71° and 109° domains with different electrical boundary conditions on the film surface, which can be controlled and manipulated through the depolarization field. The external field-sensitive enhancements of properties for BiFeO3 ultrathin films, including the polarization, magnetism and morphotropic phase boundary-relevant piezoelectric response, offer us deeper insights into the investigations of the emergent properties and phenomena of epitaxial ultrathin films under various mechanical/electrical constraints. Finally, we briefly summarize the recent progress and list open questions for future study on BiFeO3 ultrathin films.
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