The Experts below are selected from a list of 54756 Experts worldwide ranked by ideXlab platform
Alain M. Jonas - One of the best experts on this subject based on the ideXlab platform.
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Room-Temperature Magnetic Switching of the Electric Polarization in FerroElectric Nanopillars.
ACS nano, 2018Co-Authors: Shashi Poddar, Bernard Nysten, Luc Piraux, Ronggang Cai, Laurent Delannay, Alain M. JonasAbstract:MagnetoElectric layers with a strong coupling between ferroElectricity and ferromagnetism offer attractive opportunities for the design of new device architectures such as dual-channel memory and multiresponsive sensors and actuators. However, materials in which a magnetic field can switch an Electric Polarization are extremely rare, work most often only at very low temperatures, and/or comprise complex materials difficult to integrate. Here, we show that magnetostriction and flexoElectricity can be harnessed to strongly couple Electric Polarization and magnetism in a regularly nanopatterned magnetic metal/ferroElectric polymer layer, to the point that full reversal of the Electric Polarization can occur at room temperature by the sole application of a magnetic field. Experiments supported by finite element simulations demonstrate that magnetostriction produces large strain gradients at the base of the ferroElectric nanopillars in the magnetoElectric hybrid layer, translating by flexoElectricity into equi...
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Multiferroic Nanopatterned Hybrid Material with Room-Temperature Magnetic Switching of the Electric Polarization.
Advanced Materials, 2016Co-Authors: Vlad-andrei Antohe, Zhijun Hu, Bernard Nysten, Luc Piraux, Alain M. JonasAbstract:A nanopatterned hybrid layer is designed, wherein the Electric Polarization can be flipped at room temperature by a magnetic field aided by an Electrical field. This is achieved by embedding ferromagnetic nanopillars in a continuous organic ferroElectric layer, and amplifying the magnetostriction-generated stress gradients by scaling down the supracrystalline cell of the material.
Masahiro Sato - One of the best experts on this subject based on the ideXlab platform.
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High-harmonic generation by Electric Polarization, spin current, and magnetization
Physical Review B, 2019Co-Authors: Tatsuhiko N. Ikeda, Masahiro SatoAbstract:High-harmonic generation (HHG), a typical nonlinear optical effect, has been actively studied in electron systems such as semiconductors and superconductors. As a natural extension, we theoretically study HHG from Electric Polarization, spin current and magnetization in magnetic insulators under terahertz (THz) or gigahertz (GHz) electromagnetic waves. We use simple one-dimensional spin chain models with or without multiferroic coupling between spins and the Electric Polarization, and study the dynamics of the spin chain coupled to an external ac Electric or magnetic field. We map spin chains to two-band fermions and invoke an analogy of semiconductors and superconductors. With a quantum master equation and Lindblad approximation, we compute the time evolution of the Electric Polarization, spin current, and magnetization, showing that they exhibit clear harmonic peaks. We also show that the even-order HHG by magnetization dynamics can be controlled by static magnetic fields in a wide class of magnetic insulators. We propose experimental setups to observe these HHG, and estimate the required strength of the ac Electric field $E_0$ for detection as $E_0\sim100$kV/cm--1MV/cm, which corresponds to the magnetic field $B_0\sim0.1$T--1T. The estimated strength would be relevant also for experimental realizations of other theoretically-proposed nonlinear optical effects in magnetic insulators such as Floquet engineering of magnets.
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high harmonic generation by Electric Polarization spin current and magnetization
Physical Review B, 2019Co-Authors: Tatsuhiko N. Ikeda, Masahiro SatoAbstract:High-harmonic generation (HHG), a typical nonlinear optical effect, has been actively studied in electron systems such as semiconductors and superconductors. As a natural extension, we theoretically study HHG from Electric Polarization, spin current, and magnetization in magnetic insulators under terahertz or gigahertz electromagnetic waves. We use simple one-dimensional spin-chain models with or without multiferroic coupling between spins and the Electric Polarization, and study the dynamics of the spin chain coupled to an external ac Electric or magnetic field. We map spin chains to two-band fermions and invoke an analogy of semiconductors and superconductors. With a quantum master equation and Lindblad approximation, we compute the time evolution of the Electric Polarization, spin current, and magnetization, showing that they exhibit clear harmonic peaks. We also show that the even-order HHG by magnetization dynamics can be controlled by static magnetic fields in a wide class of magnetic insulators. We propose experimental setups to observe these HHGs, and estimate the required strength of the ac Electric field ${E}_{0}$ for detection as ${E}_{0}\ensuremath{\sim}100$ kV/cm--1 MV/cm, which corresponds to the magnetic field ${B}_{0}\ensuremath{\sim}0.1$ T--1 T. The estimated strength would be relevant also for experimental realizations of other theoretically proposed nonlinear optical effects in magnetic insulators such as Floquet engineering of magnets.
Bernard Nysten - One of the best experts on this subject based on the ideXlab platform.
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Room-Temperature Magnetic Switching of the Electric Polarization in FerroElectric Nanopillars.
ACS nano, 2018Co-Authors: Shashi Poddar, Bernard Nysten, Luc Piraux, Ronggang Cai, Laurent Delannay, Alain M. JonasAbstract:MagnetoElectric layers with a strong coupling between ferroElectricity and ferromagnetism offer attractive opportunities for the design of new device architectures such as dual-channel memory and multiresponsive sensors and actuators. However, materials in which a magnetic field can switch an Electric Polarization are extremely rare, work most often only at very low temperatures, and/or comprise complex materials difficult to integrate. Here, we show that magnetostriction and flexoElectricity can be harnessed to strongly couple Electric Polarization and magnetism in a regularly nanopatterned magnetic metal/ferroElectric polymer layer, to the point that full reversal of the Electric Polarization can occur at room temperature by the sole application of a magnetic field. Experiments supported by finite element simulations demonstrate that magnetostriction produces large strain gradients at the base of the ferroElectric nanopillars in the magnetoElectric hybrid layer, translating by flexoElectricity into equi...
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Multiferroic Nanopatterned Hybrid Material with Room-Temperature Magnetic Switching of the Electric Polarization.
Advanced Materials, 2016Co-Authors: Vlad-andrei Antohe, Zhijun Hu, Bernard Nysten, Luc Piraux, Alain M. JonasAbstract:A nanopatterned hybrid layer is designed, wherein the Electric Polarization can be flipped at room temperature by a magnetic field aided by an Electrical field. This is achieved by embedding ferromagnetic nanopillars in a continuous organic ferroElectric layer, and amplifying the magnetostriction-generated stress gradients by scaling down the supracrystalline cell of the material.
Luc Piraux - One of the best experts on this subject based on the ideXlab platform.
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Room-Temperature Magnetic Switching of the Electric Polarization in FerroElectric Nanopillars.
ACS nano, 2018Co-Authors: Shashi Poddar, Bernard Nysten, Luc Piraux, Ronggang Cai, Laurent Delannay, Alain M. JonasAbstract:MagnetoElectric layers with a strong coupling between ferroElectricity and ferromagnetism offer attractive opportunities for the design of new device architectures such as dual-channel memory and multiresponsive sensors and actuators. However, materials in which a magnetic field can switch an Electric Polarization are extremely rare, work most often only at very low temperatures, and/or comprise complex materials difficult to integrate. Here, we show that magnetostriction and flexoElectricity can be harnessed to strongly couple Electric Polarization and magnetism in a regularly nanopatterned magnetic metal/ferroElectric polymer layer, to the point that full reversal of the Electric Polarization can occur at room temperature by the sole application of a magnetic field. Experiments supported by finite element simulations demonstrate that magnetostriction produces large strain gradients at the base of the ferroElectric nanopillars in the magnetoElectric hybrid layer, translating by flexoElectricity into equi...
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Multiferroic Nanopatterned Hybrid Material with Room-Temperature Magnetic Switching of the Electric Polarization.
Advanced Materials, 2016Co-Authors: Vlad-andrei Antohe, Zhijun Hu, Bernard Nysten, Luc Piraux, Alain M. JonasAbstract:A nanopatterned hybrid layer is designed, wherein the Electric Polarization can be flipped at room temperature by a magnetic field aided by an Electrical field. This is achieved by embedding ferromagnetic nanopillars in a continuous organic ferroElectric layer, and amplifying the magnetostriction-generated stress gradients by scaling down the supracrystalline cell of the material.
Hiroaki Kusunose - One of the best experts on this subject based on the ideXlab platform.
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Kondo-induced Electric Polarization modulated by magnetic flux through a triangular triple quantum dot
Journal of Physics: Conference Series, 2015Co-Authors: Mikito Koga, Masashige Matsumoto, Hiroaki KusunoseAbstract:The Kondo effect plays an important role in emergence of Electric Polarization in a triangular triple-quantum-dot system, where one of the three dots is point-contacted with a single lead, and a magnetic flux penetrates through the triangular loop. The Kondo-induced Electric Polarization exhibits an Aharonov-Bohm type oscillation as a function of the magnetic flux. Our theoretical study shows various oscillation patterns associated with the field-dependent mixing of twofold orbitally degenerate ground states and their sensitivity to the point contact.
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Magnetic Flux Effect on a Kondo-Induced Electric Polarization in a Triangular Triple Quantum Dot
Journal of the Physical Society of Japan, 2014Co-Authors: Mikito Koga, Masashige Matsumoto, Hiroaki KusunoseAbstract:A magnetic flux effect is studied theoretically on an Electric Polarization induced by the Kondo effect in a triangular triple-quantum-dot system, where one of the three dots is connected to a metallic lead. This Electric Polarization exhibits an Aharonov–Bohm oscillation as a function of the magnetic flux penetrating through the triangular loop. The numerical renormalization group analysis reveals how the oscillation pattern depends on the Kondo coupling of a local spin with lead electrons, which is sensitive to the point contact with the lead. It provides an experimental implication that the Kondo effect is the origin of the emergent Electric Polarization.
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Emergent Electric Polarization by Kondo Effect in a Triangular Triple Quantum Dot
Journal of the Physical Society of Japan, 2012Co-Authors: Mikito Koga, Masashige Matsumoto, Hiroaki KusunoseAbstract:A triangular triple quantum dot gives various Kondo effects, such as the emergence of an Electric Polarization accompanied by a complete compensation of spin degrees of freedom. The interplay of sp...