Open Access. Powered by Scholars. Published by Universities.®

Physics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 19 of 19

Full-Text Articles in Physics

Tunneling Anisotropic Magnetoresistance In Ferroelectric Tunnel Junctions, Artem Alexandrov, M. Ye. Zhuravlev, Evgeny Y. Tsymbal Aug 2019

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 Aug 2019

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 Jul 2019

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 Apr 2019

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 Feb 2019

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 Feb 2019

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 Feb 2019

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 Feb 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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 Jan 2019

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.