N. S. Averkiev, I. A. Kokurin
We present here a brief overview of current-induced spin polarization in bulk semiconductors and semiconductor structures of various dimension. The role of band structure and spin relaxation processes is discussed. The related phenomena, such as spin Hall effect, inverse spin Hall effect and other are discussed. Our recent results in this field are presented as well.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
继续探索
Optical Orientation in Ferromagnet/Semiconductor Hybrids
讨论了铁磁/半导体混合结构中半导体电子的光抽运物理。光学取向的半导体电子检测铁磁膜的磁性状态。反过来，混合物的铁磁性可以在半导体的帮助下进行光学控制。铁磁体/半导体界面附近的自旋-自旋相互作用在光读出和铁磁性操纵中起着至关重要的作用。
Theory of Spin Orientation of Semiconductor Carriers at a Ferromagnetic Interface
本文提出了半导体电子与铁磁体界面处肖特基势垒自旋散射的量子理论。非极化非平衡载流子的反射在半导体中产生自发自旋极化。如果净自旋极化预先存在于半导体中，则铁磁体磁化和入射载流子极化的组合结合以倾斜半导体中的反射极化。自旋反射特性的系统特性的函数进行了研究：肖特基势垒高度，半导体掺杂和施加的偏压。由于势垒宽度与电子能量的变化对反射的影响进行了对比，两种方法的激发：光学或电学。光激发电子具有比来自非磁性欧姆接触的近平衡激发更宽的能量扩展。
Electrical control of optical orientation of neutral and negatively charged excitons in n-type semiconductor quantum well
我们报道了一个巨大的电场引起的n型GaAs/AlGaAs量子阱中激子自旋取向的增加。它与光致发光光谱中带负电荷的激子（trions）的形成密切相关。在中性重空穴激子的共振激发下，激子和trion的极化随着在PL光谱中的窄激子-trion偏置跃迁内的电子的电注入而显著增加，这意味着每伏特200%的极化灵敏度。这种效应是由包含驻留电子的量子阱界面波动（所谓的“自然”量子点）非常有效地捕获中性激子引起的。
Optical orientation of excitons in hybrid metal-semiconductor nanostructures
本研究在金属光栅近场中实现激子光学取向，产生大波矢激子，可用于研究量子阱中热激子的精细结构与动力学。
Spin-Orbit induced semiconductor spin guides
Rashba自旋轨道耦合的可调性允许构建具有空间调制耦合强度的半导体异质结构。我们表明，线形的自旋轨道调制在量子阱中可以支持传播的电子态线内只有一定的自旋取向，因此，它作为一个有效的自旋传输指南，为这个特定的自旋取向。
Interplay between Zeeman interaction and spin-orbit coupling in a two-dimensional semiconductor system
本文分析了在磁场作用下二维半导体量子系统中Dresselhaus相互作用、Bychkov-Rashba相互作用和Zeeman相互作用之间的相互作用。当被认为是一个垂直磁场，我们预测，在一个有效的回旋频率，取决于自旋相关的贡献的相互作用的结果。对于平面内的磁场，我们发现，相互作用诱导的各向异性有效旋磁因子，取决于所施加的磁场的方向，以及对电子动量的方向。
Theory of optical alignment and orientation of excitons in an ensemble of semiconductor nanoplatelets
本文提出半导体纳米片单体和ensemble中激子光学对准与取向理论，考虑亮暗激子发射及对称性，示例计算CdSe/CdS核壳结构，并展示参数波动对偏振退相的影响。
We investigate the possibility of spin-preserving symmetries due to the interplay of Rashba and Dresselhaus spin-orbit coupling in n-doped zinc-blende semiconductor quantum wells of general crystal orientation. It is shown that a conserved spin operator can be realized if and only if at least two growth-direction Miller indices agree in modulus. The according spin-orbit field has in general both in-plane and out-of-plane components and is always perpendicular to the shift vector of the corresponding persistent spin helix. We also analyze higher-order effects arising from the Dresselhaus term, …
Random fine structure and polarized luminescence of triplet excitons in semiconductor nanocrystals
研究半导体纳米晶体中三重态激子的偏振发光，通过随机精细结构理论分析发光强度、光学取向和对齐特性，探讨磁场对光学对齐的抑制和取向增强作用。
Elastic strain changes the energies of the conduction band in a semiconductor, which will affect transport through a semiconductor nanostructure. We show that the typical strains in a semiconductor nanostructure from metal gates are large enough to create strain-induced quantum dots (QDs). We simulate a commonly used QD device architecture, metal gates on bulk silicon, and show the formation of strain-induced QDs. The strain-induced QD can be eliminated by replacing the metal gates with poly-silicon gates. Thus strain can be as important as electrostatics to QD device operation operation.
Time-resolved second harmonic generation study of buried semiconductor heterointerfaces using soliton-induced transparency
同时测量了GaAs/GaSb/InAs和GaAs/GaSb异质结的瞬态二次谐波和线性反射率信号，揭示了一种基于双频电光孤子传输的窄带半导体低温自感透明的新机制.这使得在掩埋半导体异质界面的超快载流子动力学进行研究。
Magnetic flux induced spin polarization in semiconductor multichannel rings with Rashba spin orbit coupling
我们表明，一个有限的磁通量线程的多通道半导体环诱导自旋积累在样品的边界时，Rashba自旋轨道相互作用被考虑在内，即使在没有外部电场。
It is demonstrated theoretically that the circularly polarized irradiation of two-dimensional electron systems can induce the localized electron states which antiferromagnetically interact with conduction electrons, resulting in the Kondo effect. Conditions of experimental observation of the effect are discussed for semiconductor quantum wells.
Coherently photo-induced ferromagnetism in diluted magnetic semiconductors
铁磁性预测在未掺杂的稀磁半导体强烈的亚带隙激光辐射照射。光诱导铁磁性的机制是光诱导导带和价带之间的相干性，这导致光交换相互作用。铁磁临界温度T_C既取决于材料的性质，也取决于激光的频率和强度，可以在1 K以上。
Light Induced Hall effect in semiconductors with spin-orbit coupling
我们证明了在具有自旋轨道耦合的半导体中，受弱电场作用的圆偏振光的光激发电子将携带横向于电场的霍尔电流。这种光感生的霍尔效应是光和电场的量子干涉的结果，并且可以被视为由电场感生的自旋电流的物理结果。计算了p型GaAs体材料、n型和p型量子阱结构的光感生霍尔电导。
We report on a theoretical study of the electronic structures of freestanding nanowires made from narrow band gap semiconductors GaSb, InSb and InAs. The nanowires are described by the eight-band k.p Hamiltonians and the band structures are computed by means of the finite element method in a mixture basis consisting of linear triangular elements inside the nanowires and constrained Hermite triangular elements near the boundaries. The nanowires with two crystallographic orientations, namely the [001] and [111] orientations, and with different cross-sectional shapes are considered. For each orie…
Electron spin polarization induced by spin Hall effect in semiconductors with a linear in the momentum spin-orbit splitting of conduction band
结果表明，自旋霍尔效应使半导体中的电子产生均匀的自旋极化，导带的动量自旋分裂呈线性。反过来，即使在没有外部磁场的情况下，在样品边缘处积累的非均匀自旋极化的轮廓也在空间中振荡。
Effect of a uniaxial strain on optical spin orientation in cubic semiconductors
该研究通过计算价带波函数、振子强度和电子自旋极化，揭示了单轴应变下立方半导体光学自旋取向的普适性：自旋极化恒为-0.5，且不依赖应变大小和形变势，仅沿[-110]方向例外。
We study the effect of gate-induced electric fields on the properties of semiconductor-superconductor hybrid nanowires which represent a promising platform for realizing topological superconductivity and Majorana zero modes. Using a self-consistent Schrödinger-Poisson approach that describes the semiconductor and the superconductor on equal footing, we are able to access the strong tunneling regime and identify the impact of an applied gate voltage on the coupling between semiconductor and superconductor. We discuss how physical parameters such as the induced superconducting gap and Landé g-fa…
Optical orientation of electron spins by linearly polarized light
已知半导体中圆偏振光的吸收导致电子和空穴自旋的光学取向。在半导体量子阱结构中，载流子的自旋取向可以通过线性或甚至非偏振光来实现。此外，自旋取向的符号和大小可以通过旋转入射光的偏振平面来改变。研究中的效果与量子阱的对称性降低有关，与体材料相比，微观上是由电子和空穴态的零场自旋分裂引起的。
Electron Transport in Magnetic-Field-Induced Quasi-One-Dimensional Electron Systems in Semiconductor Nanowhiskers
在磁量子极限下研究了半导体纳米晶须中电子隧穿的多体效应。我们考虑的系统与体和边缘状态共存。结果表明，边缘态的相互作用参数远小于体态的相互作用参数，边缘态的隧穿电导几乎不依赖于温度，体态隧穿电导具有奇异性.
The search for half-metals and spin-gapless semiconductors has attracted extensive attention in material design for spintronics. Existing progress in such a search often requires peculiar atomistic lattice configuration and also lacks active control of the resulting electronic properties. Here we reveal that a boron-nitride nanoribbon with a carbon-doped edge can be made a half-metal or a spin-gapless semiconductor in a programmable fashion. The mechanical strain serves as the on/off switches for functions of half-metal and spin-gapless semiconductor to occur. Our findings shed light on how th…
Kinetic magnetoelectric effect in a 2D semiconductor strip due to boundary-confinement induced spin-orbit coupling
在二维半导体电子系统的薄带中，由于边界区域中限制势的显著空间变化，在带的两个边缘附近可以诱导自旋-轨道耦合。在本文中，我们表明，在边界约束诱导的自旋轨道耦合的存在下，纵向电荷电流循环通过一个二维半导体条可能会导致\textit{strong}非平衡自旋积累附近的两个边缘的带。自旋将沿着2DEG平面的法线极化，但在条带的两个边缘处以相反的方向极化。从理论观点来看，这种现象本质上是一种动力学磁电效应，但它表现出与自旋霍尔效应非常相似的形式。
Fidelity of optically induced single-spin rotations in semiconductor quantum dots in the presence of nuclear spins
我们研究了核自旋对半导体量子点中单电子自旋光致旋转的影响。我们考虑了电子自旋态之间的拉曼型光学跃迁，并考虑了Overhauser场的附加效应。我们用微扰理论在奥弗豪泽场中解析地计算了核自旋存在下绕特征轴转动的平均量子数，直到二阶。此外，我们计算的保真度使用数值平均的核场分布，包括任意阶的超精细相互作用。
Semiconductor cavity QED: Bandgap induced by vacuum fluctuations
从理论上考虑嵌入一维微腔中的半导体纳米结构，研究电磁场的真空涨落对其电子能谱的修改。为了解决这个问题，一个非微扰的图形方法的基础上的格林函数形式主义的发展。结果表明，系统与光腔真空涨落的相互作用打开了半导体价带内的能隙。该方法被验证的情况下，大的光子占据数，证明了该模型的有效性，通过与以前的研究相比，由经典电磁场激发的半导体系统。发展的理论是一般性的，并允许统一的量子和经典的描述在半导体结构中的强烈的光-物质相互作用。
Diminished Short Channel Effects in Nanoscale Double-Gate Silicon-On-Insulator Metal-Oxide- Semiconductor Field-Effect-Transistors due to Induced Back-Gate Step Potential
在这封信中，我们讨论了如何在亚100 nm沟道范围内的短沟道行为，可以通过诱导在非对称双栅（DG）绝缘体上硅（SOI）金属氧化物半导体场效应晶体管（MOSFET）的背栅阶跃表面电位分布，其中前栅由两种具有不同功函数的材料组成。
Our recent study [Phys. Rev. B 103, 085309 (2021)] verified the existence of $\bf{k}$-linear Rashba spin-orbit coupling (SOC) of two-dimensional hole gases in quantum wells (QWs) which originates from a combination of heavy-hole-light-hole (HH-LH) mixing and direct dipolar coupling to the external electric field. However, the Rashba SOC dependence on QW orientations remains unclear. Here, we explore this dependence on QW orientations and uncover an upper and lower bound to the orientation-dependent $\bf{k}$-linear Rashba SOC along the [110]- and [111]- crystalline directions by performing atom…
Optical spin transfer in ferromagnetic semiconductors
圆偏振激光脉冲，激发电子空穴对跨带隙的（III，Mn）V铁磁半导体可用于操纵和研究集体磁化动力学。a（III，V）半导体中光生载流子的初始自旋取向由激光的偏振态决定。我们表明，光生载流子自旋可以不可逆地转移到集体磁化，其动力学可以灵活地控制适当选择的激光脉冲。作为例子，我们证明了全光铁磁共振和光学磁化重定向的可行性。
Spin control in semiconductor quantum wires
我们证明了半导体量子线中由任意强度的Rashba相互作用和Dresselhaus相互作用引起的自旋翻转转动可以被面内磁场所抑制。我们发现了一种新的对称性，它出现在一组特定的强度和方向的磁场，并解释了这种抑制。根据我们的研究结果，我们提出了一个运输实验来衡量的Rashba和Dresselhaus相互作用的强度。
Within the effective-mass approximation, we theoretically investigated the electronic and transport properties of 2D semiconductor quantum wires (QWs) with anisotropic effective masses and different orientations with respect to the anisotropic axis. The energy levels in the absence and presence of an external magnetic field are analytically calculated, showing: (i) a strong dependence on the spacing of energy levels related to the alignment QW angle and the anisotropy axis; and (ii) for non-null magnetic field, the quantum Hall edge states are significantly affected by the edge orientation. Mo…
We consider the fluctuation-induced (Casimir) pressure in peptide films deposited on GaAs, Ge, and ZnS substrates which are either in dielectric or metallic state. Calculations of the Casimir pressure are performed in the framework of fundamental Lifshitz theory employing the frequency-dependent dielectric permittivities of all involved materials. The electric conductivity of semiconductor substrates is taken into account within the experimentally and thermodynamically consistent approach. According to our results, the Casimir pressure in peptide films deposited on dielectric-type semiconducto…
Using the Matsubara Green's function formalism we calculate the temperature dependence of the nonequilibrium spin polarization induced by an external electric field in the presence of spin-orbit coupling. The model Hamiltonian includes an isotropic k-cubed form of the Rashba spin-orbit interaction. Such a Hamiltonian captures the electronic and spin properties of two-dimensional electron (hole) gas at the surfaces or interfaces of transition metal oxides or in p-doped semiconductor heterostructures. The induced spin polarization is calculated for the nonmagnetic as well as magnetic electron/ho…
Anisotropic effects and phonon induced spin relaxation in gate-controlled semiconductor quantum dots
本文详细分析了各向异性对III-V族半导体量子点中声子诱导自旋弛豫速率的影响。我们发现，由于在各向同性和各向异性量子点的相反的电子自旋态的第一和第二激发态之间的水平交叉的意外简并可以操纵与应用程序的外部施加的栅极电位。特别地，除了III-V族半导体QD中的较低QD半径之外，各向异性栅极电势增强了声子介导的自旋翻转速率并将尖状结构降低到较低的磁场。在InAs量子点中，只有Rashba自旋轨道耦合对声子诱导的自旋弛豫速率有贡献。然而，对于GaAs量子点，Rashba自旋-轨道耦合的贡献附近的偶然简并点和Dresselhaus自旋-轨道耦合的贡献低于和高于偶然简并点在量子点的声子诱导的自旋弛豫率的操纵。
Many-Body Effects on Tunneling of Electrons in Magnetic-Field-Induced Quasi One-Dimensional Electron Systems in Semiconductor Nanowhiskers
在磁量子极限下研究了电子-电子相互作用对半导体纳米晶须隧穿的影响。我们考虑的系统与体和边缘状态共存。在体状态下，传输概率的温度依赖性定性地类似于一维电子系统。我们研究了体态中边缘态对透射几率的贡献。在我们的近似中，这些贡献可以忽略不计，因为我们只考虑了低温下最发散的项。
Magnetic field induced shell-to-core confinement transition in type-II semiconductor quantum wires
研究了具有II型能带失配的核-多壳层半导体纳米线在外加磁场作用下的激子性质。我们的研究结果表明，根据芯线半径，在II型带中的载流子表现出量子点样或量子环样的能谱，分别对应于芯线或外壳中的载流子限制。在后者中，壳到芯的限制转变可以通过增加磁场强度，这可能会导致有趣的光电流性质的这些限制结构，可调的外部场诱导。
Current-induced spin polarization in nonmagnetic semiconductor junctions
通过载流子散射过程，可以产生流过半导体结的电流的自发自旋极化，该过程与载流子自旋无关。电流诱导自旋极化所需的两个要素是（1）结中存在内置空间变化的电场和（2）依赖于能量的载流子散射过程。这种效应不需要自旋-轨道相互作用，因此它应该发生在像硅这样缺乏显著自旋-轨道相互作用的材料中。GaAs结中含时非线性自旋输运的近似解析表达式和详细的数值模拟结果表明，最近在该系统中观察到的电流诱导自旋极化[Y.卡托河C. Myers，A. C. Gossard和D. D. Awschalom，Phys. Rev. Lett. 93，176601（2004）]可以通过这种效应来解释。
Moderate amount of bending strains, ~3% are enough to induce the semiconductor-metal transition in Si nanowires of ~4nm diameter. The influence of bending on silicon nanowires of 1 nm to 4.3 nm diameter is investigated using molecular dynamics and quantum transport simulations. Local strains in nanowires are analyzed along with the effect of bending strain and nanowire diameter on electronic transport and the transmission energy gap. Interestingly, relatively wider nanowires are found to undergo semiconductor-metal transition at relatively lower bending strains. The effect of bending strain on…
We analyze a prototypical particle-in-a-box model for a hole spin qubit. This quantum dot is subjected to static magnetic and electric fields, and to a radio-frequency electric field that drives Rabi oscillations owing to spin-orbit coupling. We derive the equations for the Rabi frequency in a regime where the Rabi oscillations mostly result from the coupling between the qubit states and a single nearby excited state. This regime has been shown to prevail in, e.g., hole spin qubits in thin silicon-on-insulator nanowires. The equations for the Rabi frequency highlight the parameters that contro…
Theory of Optical Orientation in n-Type Semiconductors
时间分辨测量的磁化在n-GaAs揭示了一个丰富的自旋退相干过程，并已表明，相当长的寿命（\sim 100 ns），可以在某些情况下实现。在时间分辨法拉第旋转和时间分辨克尔旋转中，磁化强度的演化可以作为温度、外加场、掺杂水平和激发水平的函数来跟踪。我们提出了一个理论的自旋弛豫在n-GaAs的基础上的一组速率方程的两个相互作用的热化子系统的自旋：本地化状态的施主网站和巡回状态的导带。导带自旋通过D 'yakonov-Perel'机制从缺陷或声子散射而弛豫，而局域自旋通过与声子相互作用（当在施加的场中时）或通过Dzyaloshinskiii-Moriya相互作用而弛豫。在这个模型中，许多功能的数据，包括令人困惑的温度和掺杂的弛豫时间的依赖性，找到一个解释。
Superconducting proximity effect in semiconductor nanowires
我们从理论上考虑邻近效应的超导体-超导体混合纳米结构，这是正在进行的搜索非阿贝尔马约拉纳费米子在固态系统中的背景下，正在广泛研究。具体来说，我们认为在垂直于界面的方向上的半导体的厚度的依赖性，一个物理效应，已被不加批判地忽略在所有以前的工作中的主题。非常令人惊讶的是，我们发现了完全出乎意料的结果，增加半导体厚度导致的诱导超导能隙的急剧抑制，由于邻近诱导的带间耦合。结果表明，在强超导体-超导体耦合的极限下，邻近诱导能隙比体超导体能隙小得多，对界面透明性的依赖性很弱。
Hanle effect in current induced spin orientation
研究电流诱导自旋取向在磁性二维异质结构中的Hanle效应，分析自旋轨道耦合对自旋取向的影响及不同散射机制下的敏感性。
Stone-Wales defects can cause a metal-semiconductor transition in carbon nanotubes depending on their orientation
研究表明，碳纳米管表面的Stone-Wales（SW）缺陷具有两种不同的取向，即纵向和周向SW缺陷，导致了两种不同的电子结构。基于密度泛函理论，我们已经表明，纵向SW缺陷不打开附近的费米能的带隙，而一个相对较小的带隙出现在管与周向缺陷。我们认为，在周向SW缺陷的存在下的带隙开放是长程对称性破缺的结果，可以沿着管的所有方式传播。具体而言，由于缺陷的存在而导致的收缩和拉伸键长的分布以及低能电子（即2 pz电子）的跳跃能显示了两种类型缺陷的两种不同模式。对于不同的缺陷浓度的几何特征和电子性质的管之间的相互作用也进行了研究。考虑到$π$ -轨道电荷密度，它也已被证明，键长从其松弛长度的偏差导致在不同的掺杂的缺陷周围的两个缺陷取向-电子丰富的圆周缺陷和空穴丰富的纵向缺陷。我们还表明，在管具有两种类型的缺陷，周向缺陷将占主导地位，并施加其电子特性。
Semiconductor nanowires have been shown to exhibit novel optoelectronic properties with respect to bulk specimens made of the same material. However, if a semiconductor alloy has a miscibility gap in its phase diagram, at equilibrium it will phase separate, leading to deterioration of the aforementioned properties. One way to prevent this separation is to grow the material at low temperatures and therefore to suppress kinetics. Such growth often needs to be followed by high-temperature annealing in order to rid the system of undesirable growth-induced defects. In this study, we propose a metho…
Enhanced Coulomb interactions in monolayer transition metal dichalcogenides cause tightly bound electron-hole pairs (excitons) which dominate their linear and nonlinear optical response. The latter includes bleaching, energy renormalizations, and higher-order Coulomb correlation effects like biexcitons and excitation-induced dephasing (EID). While the first three are extensively studied, no theoretical footing for EID in exciton dominated semiconductors is available so far. In this study, we present microscopic calculations based on excitonic Heisenberg equations of motion and identify the cou…
Coulomb-induced Rashba spin-orbit coupling in semiconductor quantum wells
在没有外场的情况下，半导体量子阱中二维电子气中的Rashba自旋轨道相互作用（SOI）完全来自电离施主的屏蔽静电势。我们调整量子阱的波函数，使得占据第一（最低）子带的电子沿着生长轴（Sz）保持其自旋投影，而占据第二子带的电子由于Rashba SOI而进动。这种特殊设计的量子阱可以用作自旋弛豫触发器：当施加的电压（或电流）低于某个阈值V* 时，电子守恒Sz;较高的电压开启Dyakonov-Perel自旋弛豫。
Hyperfine interaction induced dephasing of coupled spin qubits in semiconductor double quantum dots
从理论上研究了具有有限单重态-三重态分裂J的双量子点中两电子自旋态的超精细诱导退相.特别地，我们导出了一个有效的纯退相哈密顿量，当超精细诱导混合由于相对较大的J和外部磁场而被抑制时，这个有效的纯退相哈密顿量是有效的.使用两个量子理论的基础上重申的环形图和半经典的方法，我们确定的制度所定义的外部磁场，单重态-三重态分裂的值，并在总的有效磁场的不均匀性占主导地位的退相过程。我们解决了单重态和非极化三重态叠加的自由感应和哈恩回波衰减（这两种情况都与双量子点中实现的单重态-三重态量子比特有关）。我们还研究了两个单自旋量子比特的超精细引起的交换门误差。III-V族半导体以及硅基量子点的结果。
Interface-induced Topological Insulator Transition in GaAs/Ge/GaAs Quantum Wells
我们从理论上证明了界面工程可以驱动锗，最常用的半导体之一，到拓扑绝缘相。利用电荷在GaAs/Ge/GaAs相对半导体界面的积累和能带折叠产生的巨大电场，这种新的设计可以减小Ge中相当大的能隙，并诱导大的自旋轨道相互作用，从而导致拓扑绝缘体转变。我们的工作提供了一种新的方法，实现TI在常用的半导体，并建议了一个有前途的方法，将其集成到成熟的半导体电子器件。
Electric-Field-Induced Nuclear Spin Resonance Mediated by Oscillating Electron Spin Domains in GaAs-Based Semiconductors
我们证明了一种替代的核自旋共振使用射频（RF）电场（核电共振：NER），而不是磁场。NER是基于电子自旋的电子控制，形成畴结构。施加到栅极的RF电场激发畴壁的空间振荡，并且因此激发超精细场到核自旋的时间振荡。NER谱的RF功率和突发持续时间依赖性提供了对核自旋和振荡畴壁之间的相互作用的洞察。
We study the current-driven motion of metastable localized spin structures with various topological charges in a (Pt$_{1-x}$Ir$_{x}$)/Fe bilayer on a Pd(111) surface by combining atomistic spin model simulations with an approach based on the generalized Thiele equation. We demonstrate that besides a distinct dependence on the topological charge itself the dynamic response of skyrmionic structures with topological charges $\mathrm{Q} = -1$ and $\mathrm{Q}= 3$ to a spin-polarized current exhibits an orientation dependence. We further show that such an orientation dependence can be induced by app…
Magnetically doped semiconductors are well known for their giant Zeeman splittings which can reach several meV even in relatively small external magnetic fields. After preparing a nonequilibrium exciton distribution via optical excitation, the spin dynamics in diluted magnetic semiconductor quantum wells is typically governed by spin-flip scattering processes due to the exciton-impurity exchange interaction. Our theoretical calculations show that the giant Zeeman splitting in these materials in combination with the influence of longitudinal acoustic phonons lead to a quantum ratchet-type dynam…
Spin polarized electric currents in semiconductor heterostructures induced by microwave radiation
研究了（Cd，Mn）Te/（Cd，Mg）Te和InAs/（In，Ga）As量子阱在面内磁场作用下的微波辐射感生电流.电流的产生归因于微波辐射加热的电子的自旋相关的能量弛豫。弛豫在自旋向上和自旋向下的子带中产生相等且方向相反的电子流，从而产生纯自旋电流。磁场中的子带的塞曼分裂导致自旋流转换成自旋极化的电流。
Piezoelectric rotator for studying quantum effects in semiconductor nanostructures at high magnetic fields and low temperatures
我们报告的压电样品旋转系统的设计和开发，并将其集成到牛津仪器Kelvinox 100稀释冰箱，在毫开尔文温度下，在磁场高达10 T的半导体纳米器件的量子输运的取向依赖性研究。我们的设备允许在两种可能的配置中连续原位旋转装置通过> 100度。第一个允许场在设备的平面内旋转，第二个允许场从平面内旋转到垂直于设备平面。集成的角度传感器与闭环反馈系统相结合，可使器件方位在+/-0.03度范围内，同时保持样品温度低于100 mK。
The search for exotic new topological states of matter in widely accessible materials, for which the manufacturing process is mastered, is one of the major challenges of the current topological physics. Here we predict higher order topological insulator state in quantum wells based on the most common semiconducting materials. By successively deriving the bulk and boundary Hamiltonians, we theoretically prove the existence of topological corner states due to cubic symmetry in quantum wells with double band inversion. We show that the appearance of corner states does not depend solely on the cry…
We consider theoretically a closed (zero-dimensional) semiconductor microcavity where confined vacuum photonic mode is coupled to electrons in valence band of the semiconductor. It is shown that vacuum-induced virtual electron transitions between valence and conduction bands result in renormalization of electron energy spectrum. As a consequence, vacuum-induced band gaps appear within the valence band. Calculated values of the band gaps are of sub-meV scale, that makes this QED effect to be measurable in state-of-the-art experiments.
We employ first-principles techniques tailored to properly describe semiconductors (modified Becke-Johnson potential added to the exchange-correlation functional), to obtain the electronic band structures of both the zinc-blende and wurtzite phases of GaAs, GaSb, InAs, and InSb. We extract the spin-orbit fields for the relevant valence and conduction bands at zone center, by fitting the spin-splittings resulting from the lack of space inversion symmetry of these bulk crystal structures, to known functional forms---third-order polynomials. We also determine the orientations of the spin-orbit ve…
Induced spin texture in semiconductor/topological insulator heterostructures
我们发现，半导体薄膜可以获得一个非平凡的自旋织构由于邻近效应诱导的拓扑绝缘体。该效应源于与拓扑表面态的耦合，即使绝缘体被掺杂也存在。我们提出了一种半导体/拓扑绝缘体异质结构作为一种设备，允许测量界面特性和探测未补偿样品的表面状态。我们还发现，拓扑绝缘体表面模式可以显着拓宽和移动的存在下，金属接触。
Current induced electron spin polarization in strained semiconductors
利用静态和时间分辨的法拉第旋转，在应变半导体中观察到电流引起的传导电子自旋的极化。电极化自旋的密度、寿命和取向率的特征在于光学和电学方法的组合。此外，利用光电导开关产生的电脉冲研究了电流诱导自旋的动力学。这些结果表明，不使用磁性材料的半导体自旋电子器件的自旋源的可能性。
We show that optically pumped semiconductors can exhibit superconductivity. We illustrate this phenomenon in the case of a two-band semiconductor tunnel-coupled to broad-band reservoirs and driven by a continuous wave laser. More realistically, we also show that superconductivity can be induced in a two-band semiconductor interacting with a broad-spectrum light source. We furthermore discuss the case of a three-band model in which the middle band replaces the broad-band reservoirs as the source of dissipation. In all three cases, we derive the simple conditions on the band structure, electron-…
Frequency cavity pulling induced by a single semiconductor quantum dot
本文研究了在弱耦合条件下，确定性耦合到受限光模的单个半导体量子点的发光特性。当改变发射器和腔之间的光谱失谐时，腔模发射的强拉、加宽和变窄被证明。理论上考虑了量子点跃迁的声子辅助发射。这些观察突出了一个新的情况腔量子电动力学涉及光谱宽发射器。
Direct optical detection of pure spin current in semiconductors
提出了一种利用半导体系统中光量子干涉过程（QUIP）的双色法拉第旋转直接探测纯自旋电流的新方案。从理论上证明了QUIP的法拉第旋转敏感地依赖于载流子的自旋取向和波矢，并且可以通过$ω$和$2ω$激光束的相对相位和偏振方向进行调谐。通过调整这些参数，可以检测自旋电流的大小和方向。
扫码添加微信好友，提出您的宝贵建议 👇
💡 备注请填写：网站反馈
发表机构由 AI 从论文文本抽取，如发现错误，欢迎反馈修正建议。