1
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Wang Y, Zhou P, Fetisov L, Fetisov Y, Qi Y, Zhang T. Phase Conductance of BiFeO 3 Film. SENSORS (BASEL, SWITZERLAND) 2023; 23:9123. [PMID: 38005511 PMCID: PMC10674323 DOI: 10.3390/s23229123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Revised: 11/03/2023] [Accepted: 11/09/2023] [Indexed: 11/26/2023]
Abstract
In this work, the local conductance of the tetragonal-like (T-like) and rhombohedral-like (R-like) phases of epitaxial BiFeO3 film is systematically studied via conductive atomic force microscopy. At higher tip voltage, there is a mutual transition between the T-like and R-like phases, which could be attributed to the strain relaxation in the T-like phase induced by electric poling, as well as local polarization switching. The T-like phase exhibits a higher conductance, which is related to the lower interface potential barrier between the tip and film surface. Reversible low- and high-current states in the T-like phase can be tuned by polarization switching. These results will be helpful for designing novel nanoelectronic devices, such as voltage and strain sensors.
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Affiliation(s)
- Yufeng Wang
- Ministry of Education Key Laboratory for Green Preparation and Application of Functional Materials, Hubei Provincial Key Laboratory of Polymers, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, School of Materials Science and Engineering, Hubei University, Wuhan 430062, China; (Y.W.); (T.Z.)
| | - Peng Zhou
- Ministry of Education Key Laboratory for Green Preparation and Application of Functional Materials, Hubei Provincial Key Laboratory of Polymers, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, School of Materials Science and Engineering, Hubei University, Wuhan 430062, China; (Y.W.); (T.Z.)
| | - Leonid Fetisov
- Research-Education Center “Magnetoelectric Materials and Devices”, MIREA—Russian Technological University, Moscow 119454, Russia
| | - Yuri Fetisov
- Research-Education Center “Magnetoelectric Materials and Devices”, MIREA—Russian Technological University, Moscow 119454, Russia
| | - Yajun Qi
- Ministry of Education Key Laboratory for Green Preparation and Application of Functional Materials, Hubei Provincial Key Laboratory of Polymers, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, School of Materials Science and Engineering, Hubei University, Wuhan 430062, China; (Y.W.); (T.Z.)
| | - Tianjin Zhang
- Ministry of Education Key Laboratory for Green Preparation and Application of Functional Materials, Hubei Provincial Key Laboratory of Polymers, Collaborative Innovation Center for Advanced Organic Chemical Materials Co-Constructed by the Province and Ministry, School of Materials Science and Engineering, Hubei University, Wuhan 430062, China; (Y.W.); (T.Z.)
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2
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Amrillah T, Chen YX, Duong MN, Abdussalam W, Simanjuntak FM, Chen CH, Chu YH, Juang JY. Effects of pillar size modulation on the magneto-structural coupling in self-assembled BiFeO3–CoFe2O4 heteroepitaxy. CrystEngComm 2020. [DOI: 10.1039/c9ce01573f] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The magneto-structural coupling of BiFeO3 (BFO)–CoFe2O4 (CFO)/LaAlO3 (LAO) heteroepitaxy with various lateral sizes of CFO pillars embedded in a BFO matrix was investigated.
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Affiliation(s)
- Tahta Amrillah
- Department of Physics
- Faculty of Science and Technology
- Airlangga University
- Surabaya 60115
- Indonesia
| | - Yu-Xun Chen
- Department of Electrophysics
- National Chiao Tung University
- Hsinchu 30010
- Taiwan
- National Synchrotron Radiation Research Center (NSRRC)
| | - My Ngoc Duong
- Department of Electrophysics
- National Chiao Tung University
- Hsinchu 30010
- Taiwan
| | | | | | - Chia-Hao Chen
- National Synchrotron Radiation Research Center (NSRRC)
- Hsinchu
- Taiwan
| | - Ying-Hao Chu
- Department of Electrophysics
- National Chiao Tung University
- Hsinchu 30010
- Taiwan
- Department of Materials Science and Engineering
| | - Jenh-Yih Juang
- Department of Electrophysics
- National Chiao Tung University
- Hsinchu 30010
- Taiwan
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3
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Simons H, Jakobsen AC, Ahl SR, Poulsen HF, Pantleon W, Chu YH, Detlefs C, Valanoor N. Nondestructive Mapping of Long-Range Dislocation Strain Fields in an Epitaxial Complex Metal Oxide. NANO LETTERS 2019; 19:1445-1450. [PMID: 30724569 DOI: 10.1021/acs.nanolett.8b03839] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The misfit dislocations formed at heteroepitaxial interfaces create long-ranging strain fields in addition to the epitaxial strain. For systems with strong lattice coupling, such as ferroic oxides, this results in unpredictable and potentially debilitating functionality and device performance. In this work, we use dark-field X-ray microscopy to map the lattice distortions around misfit dislocations in an epitaxial film of bismuth ferrite (BiFeO3), a well-known multiferroic. We demonstrate the ability to precisely quantify weak, long-ranging strain fields and their associated symmetry lowering without modifying the mechanical state of the film. We isolate the screw and edge components of the individual dislocations and show how they result in weak charge heterogeneities via flexoelectric coupling. We show that even systems with small lattice mismatches and additional mechanisms of stress relief (such as mechanical twinning) may still give rise to measurable charge and strain heterogeneities that extend over mesoscopic length scales. This sets more stringent physical limitations on device size, dislocation density, and the achievable degree of lattice mismatch in epitaxial systems.
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Affiliation(s)
- Hugh Simons
- Department of Physics , Technical University of Denmark , Kgs. Lyngby 2800 , Denmark
| | | | - Sonja Rosenlund Ahl
- Department of Physics , Technical University of Denmark , Kgs. Lyngby 2800 , Denmark
| | - Henning Friis Poulsen
- Department of Physics , Technical University of Denmark , Kgs. Lyngby 2800 , Denmark
| | - Wolfgang Pantleon
- Department of Mechanical Engineering , Technical University of Denmark , Kgs. Lyngby 2800 , Denmark
| | - Ying-Hao Chu
- Department of Materials Science & Engineering , National Chiao Tung University , Hsinchu 30010 , Taiwan
| | - Carsten Detlefs
- European Synchrotron Radiation Facility , 71 Avenue des Martyrs , 38043 Grenoble Cedex 9 France
| | - Nagarajan Valanoor
- School of Materials Science & Engineering , University of New South Wales , Kensington 2052 , Australia
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4
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Luo X, Tsai D, Gu M, Hong M. Extraordinary optical fields in nanostructures: from sub-diffraction-limited optics to sensing and energy conversion. Chem Soc Rev 2019; 48:2458-2494. [PMID: 30839959 DOI: 10.1039/c8cs00864g] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Along with the rapid development of micro/nanofabrication technology, the past few decades have seen the flourishing emergence of subwavelength-structured materials and interfaces for optical field engineering at the nanoscale. Three remarkable properties associated with these subwavelength-structured materials are the squeezed optical fields beyond the diffraction limit, gradient optical fields in the subwavelength scale, and enhanced optical fields that are orders of magnitude greater than the incident field. These engineered optical fields have inspired fundamental and practical advances in both engineering optics and modern chemistry. The first property is the basis of sub-diffraction-limited imaging, lithography, and dense data storage. The second property has led to the emergence of a couple of thin and planar functional optical devices with a reduced footprint. The third one causes enhanced radiation (e.g., fluorescence), scattering (e.g., Raman scattering), and absorption (e.g., infrared absorption and circular dichroism), offering a unique platform for single-molecule-level biochemical sensing, and high-efficiency chemical reaction and energy conversion. In this review, we summarize recent advances in subwavelength-structured materials that bear extraordinary squeezed, gradient, and enhanced optical fields, with a particular emphasis on their optical and chemical applications. Finally, challenges and outlooks in this promising field are discussed.
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Affiliation(s)
- Xiangang Luo
- State Key Laboratory of Optical Technologies on Nano-Fabrication and Micro-Engineering, Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu, 610209, China.
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5
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Simons H, Haugen AB, Jakobsen AC, Schmidt S, Stöhr F, Majkut M, Detlefs C, Daniels JE, Damjanovic D, Poulsen HF. Long-range symmetry breaking in embedded ferroelectrics. NATURE MATERIALS 2018; 17:814-819. [PMID: 29941920 DOI: 10.1038/s41563-018-0116-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 05/24/2018] [Indexed: 06/08/2023]
Abstract
The characteristic functionality of ferroelectric materials is due to the symmetry of their crystalline structure. As such, ferroelectrics lend themselves to design approaches that manipulate this structural symmetry by introducing extrinsic strain. Using in situ dark-field X-ray microscopy to map lattice distortions around deeply embedded domain walls and grain boundaries in BaTiO3, we reveal that symmetry-breaking strain fields extend up to several micrometres from domain walls. As this exceeds the average domain width, no part of the material is elastically relaxed, and symmetry is universally broken. Such extrinsic strains are pivotal in defining the local properties and self-organization of embedded domain walls, and must be accounted for by emerging computational approaches to material design.
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Affiliation(s)
- Hugh Simons
- Department of Physics, Technical University of Denmark, Kongens Lyngby, Denmark.
| | - Astri Bjørnetun Haugen
- Department of Energy Conversion and Storage, Technical University of Denmark, Roskilde, Denmark
| | | | - Søren Schmidt
- Department of Physics, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Frederik Stöhr
- DTU Danchip, Technical University of Denmark, Kongens Lyngby, Denmark
| | - Marta Majkut
- European Synchrotron Radiation Facility, Grenoble, France
| | | | - John E Daniels
- School of Materials Science and Engineering, UNSW Sydney, Kensington, Australia
| | - Dragan Damjanovic
- Group for Ferroelectrics and Functional Oxides, Swiss Federal Institute of Technology in Lausanne - EPFL, Lausanne, Switzerland
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6
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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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7
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Guo Y, Pu M, Li X, Ma X, Gao P, Wang Y, Luo X. Functional metasurfaces based on metallic and dielectric subwavelength slits and stripes array. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:144003. [PMID: 29339578 DOI: 10.1088/1361-648x/aaa84a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Starting with the early works of extraordinary optical transmission and extraordinary Young's interference, researchers have been fascinated by the unusual optical properties displayed by metallic holes/slits and subsequently found similar abnormities in dielectric counterparts. Benefiting from the shrinking wavelength of surface plasmon polaritons excited in metallic slits and high refractive index of dielectric stripes, one can realize local phase modulation and approach desired dispersion by engineering the geometries of a slits and stripes array. In this review, we review recent developments in functional metasurfaces composed of various metallic and dielectric subwavelength slits and stripes arrays, with special emphasis on achromatic, ultra-broadband, quasi-continuous, multifunctional and reconfigurable metasurfaces. Particular attention is paid to provide insight into the design strategies for these devices. Finally, we give an outlook of the development in this fascinating area.
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Affiliation(s)
- Yinghui Guo
- State Key Laboratory of Optical Technologies on Nano-Fabrication and Micro-Engineering, Institute of Optics and Electronics, Chinese Academy of Sciences, PO Box 350, Chengdu 610209, People's Republic of China
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8
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Bergenti I, Ruani G, Liscio F, Milita S, Dinelli F, Xu X, Wang E, Cavallini M. Highly Ordered Organic Ferroelectric DIPAB-Patterned Thin Films. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:12859-12864. [PMID: 29028341 DOI: 10.1021/acs.langmuir.7b02102] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Ferroelectric molecular compounds present great advantages for application in electronics because they combine high polarization values, comparable to those of inorganic materials, with the flexibility and low-cost properties of organic ones. However, some limitations to their applicability are related to the high crystallinity required to deploy ferroelectricity. In this article, highly ordered ferroelectric patterned thin films of diisopropylammonium bromide have been successfully fabricated by a lithographically controlled wetting technique. Confinement favors the self-organization of ferroelectric crystals, avoiding the formation of polymorphs and promoting the long-range orientation of crystallographic axes. Patterned structures present high stability, and the polarization can be switched to be arranged in stable domain pattern for application in devices.
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Affiliation(s)
| | | | | | | | | | - Xiaofeng Xu
- Chalmers University of Technology , SE-412 96 Gothenburg, Sweden
| | - Ergang Wang
- Chalmers University of Technology , SE-412 96 Gothenburg, Sweden
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9
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Tang YL, Zhu YL, Liu Y, Wang YJ, Ma XL. Giant linear strain gradient with extremely low elastic energy in a perovskite nanostructure array. Nat Commun 2017; 8:15994. [PMID: 28665413 PMCID: PMC5497064 DOI: 10.1038/ncomms15994] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Accepted: 05/18/2017] [Indexed: 11/09/2022] Open
Abstract
Although elastic strains, particularly inhomogeneous strains, are able to tune, enhance or create novel properties of some nanoscale functional materials, potential devices dominated by inhomogeneous strains have not been achieved so far. Here we report a fabrication of inhomogeneous strains with a linear gradient as giant as 106 per metre, featuring an extremely lower elastic energy cost compared with a uniformly strained state. The present strain gradient, resulting from the disclinations in the BiFeO3 nanostructures array grown on LaAlO3 substrates via a high deposition flux, induces a polarization of several microcoulomb per square centimetre. It leads to a large built-in electric field of several megavoltage per metre, and gives rise to a large enhancement of solar absorption. Our results indicate that it is possible to build up large-scale strain-dominated nanostructures with exotic properties, which in turn could be useful in the development of novel devices for electromechanical and photoelectric applications.
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Affiliation(s)
- Y L Tang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
| | - Y L Zhu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
| | - Y Liu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
| | - Y J Wang
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China
| | - X L Ma
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Wenhua Road 72, Shenyang 110016, China.,School of Materials Science and Engineering, Lanzhou University of Technology, Langongping Road 287, Lanzhou 730050, China
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10
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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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11
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Pikin SA. On the polarization dynamics in the presence of flexoelectricity and morphotropic phase boundary in ferroelectrics. CRYSTALLOGR REP+ 2017. [DOI: 10.1134/s1063774517020213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Pikin SA. On the piezoelectric properties of multiferroic nanofilms with allowance for the flexoelectric effect on morphotropic phase boundary. CRYSTALLOGR REP+ 2017. [DOI: 10.1134/s1063774517010187] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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13
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Jha PK, Jha PA, Singh P, Ranjan R, Dwivedi RK. Sm/Ti co-substituted bismuth ferrite multiferroics: reciprocity between tetragonality and piezoelectricity. Phys Chem Chem Phys 2017; 19:26285-26295. [DOI: 10.1039/c7cp01849e] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
BiFeO3 (BFO) systems co-modified with Ti, Sm and Sm–Ti have been investigated for piezoelectricity together with dielectric and multiferroic properties.
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Affiliation(s)
- Pardeep K. Jha
- Department of Physics and Materials Science and Engineering
- Jaypee Institute of Information Technology
- Noida
- India
- Department of Physics
| | - Priyanka A. Jha
- Department of Physics
- Indian Institute of Technology (Banaras Hindu University)
- Varanasi 221005
- India
| | - Prabhakar Singh
- Department of Physics
- Indian Institute of Technology (Banaras Hindu University)
- Varanasi 221005
- India
| | - Rajeev Ranjan
- Department of Materials Engineering
- Indian Institute of Science
- Bengaluru
- India
| | - R. K. Dwivedi
- Department of Physics and Materials Science and Engineering
- Jaypee Institute of Information Technology
- Noida
- India
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14
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Broadband and wide-angle RCS reduction using a 2-bit coding ultrathin metasurface at terahertz frequencies. Sci Rep 2016; 6:39252. [PMID: 27982089 PMCID: PMC5159897 DOI: 10.1038/srep39252] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 11/22/2016] [Indexed: 11/27/2022] Open
Abstract
A novel broadband and wide-angle 2-bit coding metasurface for radar cross section (RCS) reduction is proposed and characterized at terahertz (THz) frequencies. The ultrathin metasurface is composed of four digital elements based on a metallic double cross line structure. The reflection phase difference of neighboring elements is approximately 90° over a broadband THz frequency. The mechanism of RCS reduction is achieved by optimizing the coding element sequences, which redirects the electromagnetic energies to all directions in broad frequencies. An RCS reduction of less than −10 dB bandwidth from 0.7 THz to 1.3 THz is achieved in the experimental and numerical simulations. The simulation results also show that broadband RCS reduction can be achieved at an incident angle below 60° for TE and TM polarizations under flat and curve coding metasurfaces. These results open a new approach to flexibly control THz waves and may offer widespread applications for novel THz devices.
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15
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Liu J, Prashanthi K, Li Z, McGee RT, Ahadi K, Thundat T. Strain-induced electrostatic enhancements of BiFeO3 nanowire loops. Phys Chem Chem Phys 2016; 18:22772-7. [PMID: 27477993 DOI: 10.1039/c6cp03068h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Semiconductor nanowires (NWs), due to their intriguing structural and physical properties, offer tremendous potential for future technological applications. The existence of strain in NWs can greatly affect, for instance, their mechanical, electrical and optical properties. Here, we report an extraordinary electrostatic response of semiconductor BiFeO3 NW loops, based on Kelvin probe force microscopy (KPFM) and electrostatic force microscopy (EFM). A substantial ∼300 mV surface potential difference, accompanied by an ∼29% higher surface charge density, was found on the NW loop. We also found that the electrostatic enhancement is strongly related to the strain present at the curvature of the NW loops. We propose that the electric polarization coupled with mechanical strain (piezoelectric effect) or strain gradient (flexoelectricity) as possible reasons to account for our observation. These findings provide new insights into multiferroic based semiconductor NWs under external stimuli as well as significant inspiration towards strain sensors and electromechanical devices with multifunctional sensing abilities.
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Affiliation(s)
- Jun Liu
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada.
| | - Kovur Prashanthi
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada.
| | - Zhi Li
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada.
| | - Ryan T McGee
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada.
| | - Kaveh Ahadi
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada. and Materials Department, University of California, Santa Barbara, California 93106-5050, USA
| | - Thomas Thundat
- Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta T6G 2V4, Canada.
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16
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Pikin SA. Temperature dependences of the electric polarization and wave number of incommensurate structures in multiferroics. CRYSTALLOGR REP+ 2016. [DOI: 10.1134/s1063774516030214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Li Q, Cao Y, Yu P, Vasudevan RK, Laanait N, Tselev A, Xue F, Chen LQ, Maksymovych P, Kalinin SV, Balke N. Giant elastic tunability in strained BiFeO3 near an electrically induced phase transition. Nat Commun 2015; 6:8985. [PMID: 26597483 PMCID: PMC4673877 DOI: 10.1038/ncomms9985] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Accepted: 10/22/2015] [Indexed: 11/26/2022] Open
Abstract
Elastic anomalies are signatures of phase transitions in condensed matters and have traditionally been studied using various techniques spanning from neutron scattering to static mechanical testing. Here, using band-excitation elastic/piezoresponse spectroscopy, we probed sub-MHz elastic dynamics of a tip bias-induced rhombohedral−tetragonal phase transition of strained (001)-BiFeO3 (rhombohedral) ferroelectric thin films from ∼103 nm3 sample volumes. Near this transition, we observed that the Young's modulus intrinsically softens by over 30% coinciding with two- to three-fold enhancement of local piezoresponse. Coupled with phase-field modelling, we also addressed the influence of polarization switching and mesoscopic structural heterogeneities (for example, domain walls) on the kinetics of this phase transition, thereby providing fresh insights into the morphotropic phase boundary in ferroelectrics. Furthermore, the giant electrically tunable elastic stiffness and corresponding electromechanical properties observed here suggest potential applications of BiFeO3 in next-generation frequency-agile electroacoustic devices, based on the utilization of the soft modes underlying successive ferroelectric phase transitions. Ferroelectric materials possess spontaneous electrical polarization coupled to their underlying lattice structure, which may be utilized technologically. Here, the authors use band-excitation piezoresponse/elastic spectroscopy to study the sub-megahertz dynamics of a structural phase transition in BiFeO3.
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Affiliation(s)
- Q Li
- Center for Nanophase Materials Sciences and Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Y Cao
- Center for Nanophase Materials Sciences and Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - P Yu
- State Key Laboratory for Low-Dimensional Quantum Physics, Department of Physics and Collaborative Innovation Center for Quantum Matter, Tsinghua University, Beijing 100084, China.,RIKEN Center for Emergent Matter Science (CEMS), Wako, Saitama 351-0198, Japan
| | - R K Vasudevan
- Center for Nanophase Materials Sciences and Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - N Laanait
- Center for Nanophase Materials Sciences and Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - A Tselev
- Center for Nanophase Materials Sciences and Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - F Xue
- Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - L Q Chen
- Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - P Maksymovych
- Center for Nanophase Materials Sciences and Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - S V Kalinin
- Center for Nanophase Materials Sciences and Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - N Balke
- Center for Nanophase Materials Sciences and Institute for Functional Imaging of Materials, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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