本文研究了弹性散射体存在于半导体量子环的一个臂中时,电子输运通过具有一个输入端和两个输出端的半导体量子环的输运。我们表明,散射体不仅引入了不对称的传输概率的两个输出引线,但也降低了Aharonov-Bohm电导振荡的可见性。这种减少发生在尽管弹性散射的相位相干性,是由于中断的电子循环周围的环的潜在缺陷。结果与Strambini等人最近的实验[Phys. Rev. B { \bf 79},195443(2009)]定性一致。我们还指出,在实验中获得的两个输出引线的电导之和的磁对称性可以理解为从反向散射的输入引线相对于磁场方向的不变性。
英文摘要:
We study electron transport through a semiconductor quantum ring with one input and two output terminals for an elastic scatterer present within one of the arms of the ring. We demonstrate that the scatterer not only introduces asymmetry in the transport probability to the two output leads but also reduces the visibility of the Aharonov-Bohm conductance oscillations. This reduction occurs in spite of the phase coherence of the elastic scattering and is due to interruption of the electron circulation around the ring by the potential defect. The results are in a qualitative agreement with a recent experiment by Strambini et al. [Phys. Rev. B {\bf 79}, 195443 (2009)]. We also indicate that the magnetic symmetry of the sum of conductance of both the output leads as obtained in the experiment can be understood as resulting from the invariance of backscattering to the input lead with respect to the magnetic field orientation.
Spin-charge conversion in multiterminal Aharonov-Casher ring coupled to precessing ferromagnets: A charge conserving Floquet-nonequilibrium Green function approach
我们导出了描述开放量子系统的Floquet非平衡格林函数(Floquet-NEGF)的非微扰解.通过采用减少区域计划,我们得到的表达式呈现保守的电荷电流为任何给定的最大数量的光子,区别于其他现有的Floquet-NEGF为基础的表达式,不太可行,无限数量的光子需要考虑到,以确保守恒。为了证明我们导出的形式主义和研究自旋-电荷转换的自旋轨道耦合(SOC),我们认为自旋驱动的设置作为互易的电驱动设置在S。Souma et.例如,B 70,195346(2004)和Phys. Rev. Lett. 94,106602(2005)。在我们的设置中,纯自旋电流由旋进铁磁(FM)岛的磁化动力学驱动,然后被泵入Rashba SOC的相邻两端或四端介观Aharonov-Casher(AC)环,在那里发生自旋-电荷转换。我们的自旋驱动的结果显示出互惠的功能,非常同意在上述电驱动的设置中的发现。我们提出了两种对称操作,下的交流环哈密顿量是不变的,论证了泵/转换电流的关系,在同一个或不同的泵配置的引线。对称性参数与环宽度和引线、端子和旋进FM岛中的开放通道的数量无关。特别地,对于两个端子和两个旋进FM岛的某些设置,可以在引线中产生净纯平面内自旋电流和纯自旋电流,其中电流幅度和偏振方向可通过泵浦配置来调节。覆盖FM岛之间的双端AC环的栅极电压。
Stationary transport in mesoscopic hybrid structures with contacts to superconducting and normal wires. A Green's function approach for multiterminal setups
Quantum-interference-controlled three-terminal molecular transistors based on a single ring-shaped-molecule connected to graphene nanoribbon electrodes
Magnetoelastic conversion in integrated YIG nanostructures
Delft University of Technology(代尔夫特理工大学);Institute of Magnetism of NAS and MOS of Ukraine(乌克兰国家科学院和教育部磁性研究所);RWTH Aachen University(亚琛工业大学);Max Planck Institute for the Science of Light(马克斯·普朗克光科学研究所);Luxembourg Institute of Science & Technology (LIST)(卢森堡科学与技术研究所);Université Grenoble Alpes(格勒诺布尔阿尔卑斯大学);CEA(法国原子能和替代能源委员会);CNRS(法国国家科学研究中心);Grenoble INP(格勒诺布尔理工学院);Spintec(自旋电子学与技术中心);WPI-AIMR, Tohoku University(东北大学世界顶尖科学研究学院);University of the Chinese Academy of Sciences(中国科学院大学)