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- Keyword
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- Films (5)
- Heterostructures (5)
- Interface (5)
- Magnetoresistance (4)
- Electroresistance (3)
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- Magnetic tunnel junctions (3)
- Oxide Interfaces (3)
- Polarization (3)
- Spintronics (3)
- Thin-Films (3)
- Antiferromagnetic (2)
- Antiperovskite (2)
- Augmented-Wave Method (2)
- BaTiO3 (2)
- Band structure (2)
- Density functional theory (2)
- Dielectric polarisation (2)
- Electronic structure (2)
- Enhancement (2)
- Ferroelectric (2)
- Ferroelectric Tunnel Junctions (2)
- Ferroelectricity (2)
- First-principles (2)
- HfO2 (2)
- Insulators (2)
- Laalo3/Srtio3 Interface (2)
- Magnetic anisotropy (2)
- Magnetism (2)
- Magnetocrystalline anisotropy (2)
- Optical-Properties (2)
Articles 31 - 60 of 151
Full-Text Articles in Physics
Detection Of Decoupled Surface And Bulk States In Epitaxial Orthorhombic Sriro3 Thin Films, P. E. Evans, T. Komesu, L. Zhang, D.-F. Shao, A. J. Yost, S. Kumar, E. F. Schwier, K. Shimada, E. Y. Tsymbal, X. Hong, And P. A. Dowben
Detection Of Decoupled Surface And Bulk States In Epitaxial Orthorhombic Sriro3 Thin Films, P. E. Evans, T. Komesu, L. Zhang, D.-F. Shao, A. J. Yost, S. Kumar, E. F. Schwier, K. Shimada, E. Y. Tsymbal, X. Hong, And P. A. Dowben
Evgeny Tsymbal Publications
No abstract provided.
Spin-Torque Switching Of Non-Collinear Antiferromagnetic Antiperovskites, G. Gurung, D.-F. Shao, And E. Y. Tsymbal
Spin-Torque Switching Of Non-Collinear Antiferromagnetic Antiperovskites, G. Gurung, D.-F. Shao, And E. Y. Tsymbal
Evgeny Tsymbal Publications
No abstract provided.
Epitaxial Antiperovskite/Perovskite Heterostructures For Materials Design, C. X. Quintela, K. Song, D. F. Shao, L. Xie, T. Nan, T. R. Paudel, N. Campbell, X. Pan, T. Tybell, M. S. Rzchowski, E. Y. Tsymbal, S.-Y. Choi, And C.-B. Eom
Epitaxial Antiperovskite/Perovskite Heterostructures For Materials Design, C. X. Quintela, K. Song, D. F. Shao, L. Xie, T. Nan, T. R. Paudel, N. Campbell, X. Pan, T. Tybell, M. S. Rzchowski, E. Y. Tsymbal, S.-Y. Choi, And C.-B. Eom
Evgeny Tsymbal Publications
No abstract provided.
Controlling Spin Current Polarization Through Non-Collinear Antiferromagnetism, T. Nan, C. X. Quintela, J. Irwin, G. Gurung, D. F. Shao, J. Gibbons, N. Campbell, K. Song, S. Y. Choi, L. Guo, R. D. Johnson, P. Manuel, R. V. Chopdekar, I. Hallsteinsen, T. Tybell, P. J. Ryan, J. W. Kim, Y. S. Choi, P. Radaelli, D. Ralph, E. Y. Tsymbal, M. S. Rzchowski, And C. B. Eom
Controlling Spin Current Polarization Through Non-Collinear Antiferromagnetism, T. Nan, C. X. Quintela, J. Irwin, G. Gurung, D. F. Shao, J. Gibbons, N. Campbell, K. Song, S. Y. Choi, L. Guo, R. D. Johnson, P. Manuel, R. V. Chopdekar, I. Hallsteinsen, T. Tybell, P. J. Ryan, J. W. Kim, Y. S. Choi, P. Radaelli, D. Ralph, E. Y. Tsymbal, M. S. Rzchowski, And C. B. Eom
Evgeny Tsymbal Publications
No abstract provided.
Insulator-To-Conductor Transition Controlled By The Rashba-Zeeman Effect, L. L. Tao And E. Y. Tsymbal
Insulator-To-Conductor Transition Controlled By The Rashba-Zeeman Effect, L. L. Tao And E. Y. Tsymbal
Evgeny Tsymbal Publications
No abstract provided.
Ferroelectric-Driven Tunable Magnetism In Ultrathin Platinum Films, Q. Sun, F. Mahfouzi, J. P. Velev, E. Y. Tsymbal, And N. Kioussis
Ferroelectric-Driven Tunable Magnetism In Ultrathin Platinum Films, Q. Sun, F. Mahfouzi, J. P. Velev, E. Y. Tsymbal, And N. Kioussis
Evgeny Tsymbal Publications
No abstract provided.
Unveiling Multiferroic Proximity Effect In Graphene, F. Ibrahim, A. Hallal, D. S. Lerma, X. Waintal, E. Y. Tsymbal, And M. Chshiev
Unveiling Multiferroic Proximity Effect In Graphene, F. Ibrahim, A. Hallal, D. S. Lerma, X. Waintal, E. Y. Tsymbal, And M. Chshiev
Evgeny Tsymbal Publications
No abstract provided.
Strain-Driven Disproportionation At A Correlated Oxide Metal-Insulator Transition, T. H. Kim, T. R. Paudel, R. J. Green, K. Song, H.-S. Lee, S.-Y. Choi, J. Irwin, B. Noesges, L. J. Brillson, M. S. Rzchowski, G. A. Sawatzky, E. Y. Tsymbal, And C. B. Eom
Strain-Driven Disproportionation At A Correlated Oxide Metal-Insulator Transition, T. H. Kim, T. R. Paudel, R. J. Green, K. Song, H.-S. Lee, S.-Y. Choi, J. Irwin, B. Noesges, L. J. Brillson, M. S. Rzchowski, G. A. Sawatzky, E. Y. Tsymbal, And C. B. Eom
Evgeny Tsymbal Publications
No abstract provided.
Tunneling Anisotropic Magnetoresistance In Ferroelectric Tunnel Junctions, Artem Alexandrov, M. Ye. Zhuravlev, Evgeny Y. Tsymbal
Tunneling Anisotropic Magnetoresistance In Ferroelectric Tunnel Junctions, Artem Alexandrov, M. Ye. Zhuravlev, Evgeny Y. Tsymbal
Evgeny Tsymbal Publications
Using a simple quantum-mechanical model, we explore a tunneling anisotropic magnetoresistance (TAMR) effect in ferroelectric tunnel junctions (FTJs) with a ferromagnetic electrode and a ferroelectric barrier layer, where spontaneous polarization gives rise to the Rashba and Dresselhaus spin-orbit coupling (SOC). For realistic parameters of the model, we predict sizable TAMR measurable experimentally. For asymmetric FTJs, whose electrodes have different work functions, the built-in electric field affects the SOC parameters and leads to TAMR being dependent on the ferroelectric polarization direction. The SOC change with polarization switching affects tunneling conductance, revealing an alternative mechanism of tunneling electroresistance. These results demonstrate alternative …
Magnetoelectric Effect At The Ni/Hfo2 Interface Induced By Ferroelectric Polarization, Qiong Yang, Lingling Tao, Zhen Jiang, Yichun Zhou, Evgeny Tsymbal, Vitaly Alexandrov
Magnetoelectric Effect At The Ni/Hfo2 Interface Induced By Ferroelectric Polarization, Qiong Yang, Lingling Tao, Zhen Jiang, Yichun Zhou, Evgeny Tsymbal, Vitaly Alexandrov
Evgeny Tsymbal Publications
Driven by the technological importance of the recently discovered ferroelectric HfO2, we explore a magnetoelectric effect at the HfO2-based ferroelectric-ferromagnetic interface. Using density-functionaltheory calculations of the Ni/HfO2/Ni (001) heterostructure as a model system, we predict a stable and sizable ferroelectric polarization in a few-nm-thick HfO2 layer. For the Ni/HfO2 interface with opposite polarization directions (pointing to or away from the interface), we find a sizable difference in the interfacial Ni—O bonding, resulting in dissimilar degrees of depletion of the electron density around the interface. The latter affects the relative population of the …
A Room-Temperature Ferroelectric Semimetal, Pankaj Sharma, Fei-Xiang Xiang, Ding-Fu Shao, Dawei Zhang, Evgeny Y. Tsymbal, Alex R. Hamilton, Jan Seidel
A Room-Temperature Ferroelectric Semimetal, Pankaj Sharma, Fei-Xiang Xiang, Ding-Fu Shao, Dawei Zhang, Evgeny Y. Tsymbal, Alex R. Hamilton, Jan Seidel
Evgeny Tsymbal Publications
Coexistence of reversible polar distortions and metallicity leading to a ferroelectric metal, first suggested by Anderson and Blount in 1965, has so far remained elusive. Electrically switchable intrinsic electric polarization, together with the direct observation of ferroelectric domains, has not yet been realized in a bulk crystalline metal, although incomplete screening by mobile conduction charges should, in principle, be possible. Here, we provide evidence that native metallicity and ferroelectricity coexist in bulk crystalline van der Waals WTe2 by means of electrical transport, nanoscale piezoresponse measurements, and first-principles calculations. We show that, despite being a Weyl semimetal, WTe2 has switchable spontaneous …
Anomalous Hall Conductivity Of Noncollinear Magnetic Antiperovskites, Gautam Gurung, Ding-Fu Shao, Tula R. Paudel, Evgeny Y. Tsymbal
Anomalous Hall Conductivity Of Noncollinear Magnetic Antiperovskites, Gautam Gurung, Ding-Fu Shao, Tula R. Paudel, Evgeny Y. Tsymbal
Evgeny Tsymbal Publications
The anomalous Hall effect (AHE) is a well-known fundamental property of ferromagnetic metals, commonly associated with the presence of a net magnetization. Recently, an AHE has been discovered in noncollinear antiferromagnetic (AFM) metals. Driven by nonvanishing Berry curvature of AFM materials with certain magnetic space-group symmetry, anomalous Hall conductivity (AHC) is very sensitive to the specific type of magnetic ordering. Here, we investigate the appearance of AHC in antiperovskite materials family ANMn3 (A = Ga, Sn, Ni), where different types of noncollinear magnetic ordering can emerge. Using symmetry analyses and first-principles density-functional theory calculations, we show that with almost …
Dirac Nodal Line Metal For Topological Antiferromagnetic Spintronics, Ding-Fu Shao, Gautam Gurung, Shu-Hui Zhang, Evgeny Y. Tsymbal
Dirac Nodal Line Metal For Topological Antiferromagnetic Spintronics, Ding-Fu Shao, Gautam Gurung, Shu-Hui Zhang, Evgeny Y. Tsymbal
Evgeny Tsymbal Publications
Topological antiferromagnetic (AFM) spintronics is an emerging field of research, which exploits the N´eel vector to control the topological electronic states and the associated spin-dependent transport properties. A recently discovered N´eel spin-orbit torque has been proposed to electrically manipulate Dirac band crossings in antiferromagnets; however, a reliable AFM material to realize these properties in practice is missing. In this Letter, we predict that room-temperature AFM metal MnPd2 allows the electrical control of the Dirac nodal line by the N´eel spin-orbit torque. Based on first-principles density functional theory calculations, we show that reorientation of the N´eel vector leads to switching …
Electrically Reversible Magnetization At The Antiperovskite/Perovskite Interface, Ding-Fu Shao, Gautam Gurung, Tula R. Paudel, Evgeny Y. Tsymbal
Electrically Reversible Magnetization At The Antiperovskite/Perovskite Interface, Ding-Fu Shao, Gautam Gurung, Tula R. Paudel, Evgeny Y. Tsymbal
Evgeny Tsymbal Publications
Using density-functional calculations, we predict the emergence of electrically reversible magnetization at the interface between antiferromagnetic noncollinear antiperovskite GaNMn3 and ferroelectric perovskite BaTiO3. We find that Mn magnetic moments are enhanced and reoriented at the GaNMn3/ATiO3 (001) (A = Sr and Ba) interface, resulting in a sizable net magnetization along the [110] direction. This magnetization is reversed with ferroelectric polarization of BaTiO3 through ∼20◦ rotation of the noncollinear magnetic moments. The effect is driven by ferroelectric modulation of the antiferromagnetic exchange coupling between the interfacial Mn atoms mediated by the Mn-3d orbital population. Our results open opportunities for controlling the …
Ferroelectric Polarization Control Of Magnetic Anisotropy In Pbzr0.2ti0.8o3/La0.8sr0.2mno3 Heterostructures, Anil Rajapitamahuni, L. L. Tao, Y. Hao, Jingfeng Song, Xiaoshan Xu, Evgeny Y. Tsymbal, Xia Hong
Ferroelectric Polarization Control Of Magnetic Anisotropy In Pbzr0.2ti0.8o3/La0.8sr0.2mno3 Heterostructures, Anil Rajapitamahuni, L. L. Tao, Y. Hao, Jingfeng Song, Xiaoshan Xu, Evgeny Y. Tsymbal, Xia Hong
Evgeny Tsymbal Publications
The interfacial coupling between the switchable polarization and neighboring magnetic order makes ferroelectric/ferromagnetic composite structures a versatile platform to realize voltage control of magnetic anisotropy. We report the nonvolatile ferroelectric field effect modulation of the magnetocrystalline anisotropy (MCA) in epitaxial PbZr0.2Ti0.8O3 (PZT)/La0.8Sr0.2MnO3 (LSMO) heterostructures grown on (001) SrTiO3 substrates. Planar Hall effect measurements show that the in-plane magnetic anisotropy energy in LSMO is enhanced by about 22% in the hole accumulation state compared to the depletion state, in quantitative agreement with our first-principles density functional theory calculations. Modeling the …
Enhanced Flexoelectricity At Reduced Dimensions Revealed By Mechanically Tunable Quantum Tunnelling, Saikat Das, Bo Wang, Tula R. Paudel, Sung Min Park, Evgeny Y. Tsymbal, Long-Qing Chen, Daesu Lee, Tae Won Noh
Enhanced Flexoelectricity At Reduced Dimensions Revealed By Mechanically Tunable Quantum Tunnelling, Saikat Das, Bo Wang, Tula R. Paudel, Sung Min Park, Evgeny Y. Tsymbal, Long-Qing Chen, Daesu Lee, Tae Won Noh
Evgeny Tsymbal Publications
Flexoelectricity is a universal electromechanical coupling effect whereby all dielectric materials polarise in response to strain gradients. In particular, nanoscale flexoelectricity promises exotic phenomena and functions, but reliable characterisation methods are required to unlock its potential. Here, we report anomalous mechanical control of quantum tunnelling that allows for characterising nanoscale flexoelectricity. By applying strain gradients with an atomic force microscope tip, we systematically polarise an ultrathin film of otherwise nonpolar SrTiO3, and simultaneously measure tunnel current across it. The measured tunnel current exhibits critical behaviour as a function of strain gradients, which manifests large modification of tunnel barrier …
Domain-Wall Tunneling Electroresistance Effect, M. Li, L. L. Tao, And E. Y. Tsymbal
Domain-Wall Tunneling Electroresistance Effect, M. Li, L. L. Tao, And E. Y. Tsymbal
Evgeny Tsymbal Publications
No abstract provided.
Two-Dimensional Spin-Valley Locking Spin Valve, L. L. Tao And E. Y. Tsymbal
Two-Dimensional Spin-Valley Locking Spin Valve, L. L. Tao And E. Y. Tsymbal
Evgeny Tsymbal Publications
No abstract provided.
Magnetoelectric Control Of Topological Phases In Graphene, H. Takenaka, S. Sandhoefner, A. A. Kovalev, And E. Y. Tsymbal
Magnetoelectric Control Of Topological Phases In Graphene, H. Takenaka, S. Sandhoefner, A. A. Kovalev, And E. Y. Tsymbal
Evgeny Tsymbal Publications
No abstract provided.
Ferroelectric Tunnel Junctions Enhanced By A Polar Oxide Barrier Layer, Q. Yang, L. L. Tao, E. Y. Tsymbal, And V. Alexandrov
Ferroelectric Tunnel Junctions Enhanced By A Polar Oxide Barrier Layer, Q. Yang, L. L. Tao, E. Y. Tsymbal, And V. Alexandrov
Evgeny Tsymbal Publications
No abstract provided.
Atomic-Scale Control Of Magnetism At The Titanite-Manganite Interfaces, H. Wang, X. Chi, Z. R. Liu, H. Y. Yoong, L. L. Tao, J. X. Xiao, R. Guo, J. X. Wang, Z. L. Dong, P. Yang, C. J. Sun, J. Wang, G. M. Chow, E. Y. Tsymbal, H. Tian, And J. S. Chen
Atomic-Scale Control Of Magnetism At The Titanite-Manganite Interfaces, H. Wang, X. Chi, Z. R. Liu, H. Y. Yoong, L. L. Tao, J. X. Xiao, R. Guo, J. X. Wang, Z. L. Dong, P. Yang, C. J. Sun, J. Wang, G. M. Chow, E. Y. Tsymbal, H. Tian, And J. S. Chen
Evgeny Tsymbal Publications
No abstract provided.
Controlling The Magnetic Properties Of Lamno3/Srtio3 Heterostructures By Stoichiometry And Electronic Reconstruction: Atomic-Scale Evidence, M. S. Li, C. H. Tang, T. R. Paudel, D. S. Song, W. M. Lü, K. Han, Z. Huang, S. W. Zeng, X. R. Wang, P. Yang, Ariando, J. S. Chen, T. Venkatesan, E. Y. Tsymbal, C. J. Li, And S. J. Pennycook
Controlling The Magnetic Properties Of Lamno3/Srtio3 Heterostructures By Stoichiometry And Electronic Reconstruction: Atomic-Scale Evidence, M. S. Li, C. H. Tang, T. R. Paudel, D. S. Song, W. M. Lü, K. Han, Z. Huang, S. W. Zeng, X. R. Wang, P. Yang, Ariando, J. S. Chen, T. Venkatesan, E. Y. Tsymbal, C. J. Li, And S. J. Pennycook
Evgeny Tsymbal Publications
No abstract provided.
Spin Filtering In Cri3 Tunnel Junctions, T. R. Paudel And E. Y. Tsymbal
Spin Filtering In Cri3 Tunnel Junctions, T. R. Paudel And E. Y. Tsymbal
Evgeny Tsymbal Publications
No abstract provided.
Anisotropic Spin-Orbit Torque Generation In Epitaxial Sriro3 By Symmetry Design, T. Nan, T. J. Anderson, J. Gibbons, K. Hwang, N. Campbell, H. Zhou, Y. Q. Dong, G. Y. Kim, D. F. Shao, T. R. Paudel, N. Reynolds, X. J. Wang, N. X. Sun, E. Y. Tsymbal, S. Y. Choi, M. S. Rzchowski, Y. B. Kim, D. C. Ralph And C. B. Eom
Anisotropic Spin-Orbit Torque Generation In Epitaxial Sriro3 By Symmetry Design, T. Nan, T. J. Anderson, J. Gibbons, K. Hwang, N. Campbell, H. Zhou, Y. Q. Dong, G. Y. Kim, D. F. Shao, T. R. Paudel, N. Reynolds, X. J. Wang, N. X. Sun, E. Y. Tsymbal, S. Y. Choi, M. S. Rzchowski, Y. B. Kim, D. C. Ralph And C. B. Eom
Evgeny Tsymbal Publications
No abstract provided.
Spin-Dependent Transport In Van Der Waals Magnetic Tunnel Junctions With Fe3gete2 Electrodes, X. L. Li, J.-T. Lü, J. Zhang, Y. R. Su, And E. Y. Tsymbal
Spin-Dependent Transport In Van Der Waals Magnetic Tunnel Junctions With Fe3gete2 Electrodes, X. L. Li, J.-T. Lü, J. Zhang, Y. R. Su, And E. Y. Tsymbal
Evgeny Tsymbal Publications
No abstract provided.
Freestanding Crystalline Oxide Perovskites Down To The Monolayer Limit, D. X. Ji, S. H. Cai, T. R. Paudel, H. Y. Sun, C. C. Zhang, Y. F. Wei, Y. P. Zang, M. Gu, L. Han, Y. Zhang, W. P. Gao, H. X. Huyan, W. Guo, D. Wu, Z. B. Gu, E. Y. Tsymbal, P. Wang, Y. F. Nie, And X. Q. Pan
Freestanding Crystalline Oxide Perovskites Down To The Monolayer Limit, D. X. Ji, S. H. Cai, T. R. Paudel, H. Y. Sun, C. C. Zhang, Y. F. Wei, Y. P. Zang, M. Gu, L. Han, Y. Zhang, W. P. Gao, H. X. Huyan, W. Guo, D. Wu, Z. B. Gu, E. Y. Tsymbal, P. Wang, Y. F. Nie, And X. Q. Pan
Evgeny Tsymbal Publications
No abstract provided.
Polarization-Dependent Electric Potential Distribution Across Nanoscale Ferroelectric Hf0.5zr0.5o2 In Functional Memory Capacitors, Y. Matveyev, V. Mikheev, D. Negrov, S. Zarubin, A. Kumar, E. D. Grimley, J. M. Lebeau, A. Gloskovskii, E. Y. Tsymbal, And A. Zenkevich
Polarization-Dependent Electric Potential Distribution Across Nanoscale Ferroelectric Hf0.5zr0.5o2 In Functional Memory Capacitors, Y. Matveyev, V. Mikheev, D. Negrov, S. Zarubin, A. Kumar, E. D. Grimley, J. M. Lebeau, A. Gloskovskii, E. Y. Tsymbal, And A. Zenkevich
Evgeny Tsymbal Publications
No abstract provided.
Tunable Two-Dimensional Dirac Nodal Nets, Ding-Fu Shao, Shu-Hui Zhang, Xiaoqian Dang, Evgeny Y. Tsymbal
Tunable Two-Dimensional Dirac Nodal Nets, Ding-Fu Shao, Shu-Hui Zhang, Xiaoqian Dang, Evgeny Y. Tsymbal
Evgeny Tsymbal Publications
Nodal-line semimetals are characterized by symmetry-protected band crossing lines and are expected to exhibit nontrivial electronic properties. Connections of the multiple nodal lines, resulting in nodal nets, chains, or links, are envisioned to produce even more exotic quantum states. In this work, we propose a feasible approach to realize tunable nodal-line connections in real materials. We show that certain space group symmetries support the coexistence of the planar symmetry-enforced and accidental nodal lines, which are robust to spin-orbit coupling and can be tailored into intricate patterns by chemical substitution, pressure, or strain. Based on first-principles calculations, we identify nonsymmorphic centrosymmetric …
Two-Dimensional Type-Ii Dirac Fermions In A Laalo3/Lanio3/Laalo3 Quantum Well, L. L. Tao, Evgeny Y. Tsymbal
Two-Dimensional Type-Ii Dirac Fermions In A Laalo3/Lanio3/Laalo3 Quantum Well, L. L. Tao, Evgeny Y. Tsymbal
Evgeny Tsymbal Publications
The type-II Dirac fermions that are characterized by a tilted Dirac cone and anisotropic magnetotransport properties have been recently proposed theoretically and confirmed experimentally. Here, we predict the emergence of two-dimensional (2D) type-II Dirac fermions in LaAlO3/LaNiO3/LaAlO3 quantum-well structures. Using first-principles calculations and model analyses, we show that the Dirac points are formed at the crossing between the dx2−y2 and dz2 bands protected by the mirror symmetry. The energy position of the Dirac points can be tuned to appear at the Fermi energy by changing the quantum-well width. For …
Direct Observation Of Room-Temperature Out-Of-Plane Ferroelectricity And Tunneling Electroresistance At The Two-Dimensional Limit, H. Wang, Z R. Liu, H. Y. Yoong, Tula R. Paudel, J. X. Xia, R. Guo, W. N. Lin, P. Yang, J. Wang, G. M. Chow, T. Venkatesan, Evgeny Y. Tsymbal, H. Tian, J. S. Chen
Direct Observation Of Room-Temperature Out-Of-Plane Ferroelectricity And Tunneling Electroresistance At The Two-Dimensional Limit, H. Wang, Z R. Liu, H. Y. Yoong, Tula R. Paudel, J. X. Xia, R. Guo, W. N. Lin, P. Yang, J. Wang, G. M. Chow, T. Venkatesan, Evgeny Y. Tsymbal, H. Tian, J. S. Chen
Evgeny Tsymbal Publications
Out-of-plane ferroelectricity with a high transition temperature in nanometer-scale films is required to miniaturize electronic devices. Direct visualization of stable ferroelectric polarization and its switching behavior in atomically thick films is critical for achieving this goal. Here, ferroelectric order at room temperature in the two-dimensional limit is demonstrated in tetragonal BiFeO3 ultrathin films. Using aberration-corrected scanning transmission electron microscopy, we directly observed robust out-of-plane spontaneous polarization in one-unitcell-thick BiFeO3 films. High-resolution piezoresponse force microscopy measurements show that the polarization is stable and switchable, whereas a tunneling electroresistance effect of up to 370% is achieved in BiFeO3 films. …