量子点中自旋极化电子的瞬态充放电
Transient Charging and Discharging of Spin-polarized Electrons in a Quantum Dot
摘要：
本文研究了在矩形偏压脉冲作用下，耦合到两个铁磁引线上的量子点中自旋极化瞬态输运。时间相关的自旋分辨电流，职业，自旋积累和隧道磁电阻（TMR）的计算使用非平衡格林函数和主方程技术。平行和反平行引线的磁化取向进行了分析。我们的主要发现是：随时间改变符号的动态自旋累积、发射极引线中（但不在集电极引线中）自旋极化电流的短暂脉冲以及在瞬态状态中产生负值的动态TMR。我们还观察到，点内库仑相互作用可以进一步增强TMR的负值。
英文摘要：
We study spin-polarized transient transport in a quantum dot coupled to two ferromagnetic leads subjected to a rectangular bias voltage pulse. Time-dependent spin-resolved currents, occupations, spin accumulation, and tunneling magnetoresistance (TMR) are calculated using both nonequilibrium Green function and master equation techniques. Both parallel and antiparallel leads' magnetization alignments are analyzed. Our main findings are: a dynamical spin accumulation that changes sign in time, a short-lived pulse of spin polarized current in the emitter lead (but not in the collector lead), and a dynamical TMR that develops negative values in the transient regime. We also observe that the intra-dot Coulomb interaction can enhance even further the negative values of the TMR.
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。
