研究在自旋轨道耦合和周期振动场的作用下,电子隧穿双量子阱结构的透射系数和自旋极化率.通过数值计算发现:隧穿后电子的自旋简并消除,得到与自旋相关的共振峰.电子隧穿宽势阱时出现对称的Breit-Wigner共振峰,而隧穿窄势阱时出现不对称的Fano共振峰.研究也发现通过调节入射能量和中间势垒的宽度,可以改变共振峰的振幅和位置.利用这个原理可以设计可调的自旋过滤器,实现对自旋的调控.
Investigated the electronic transmission probability and spin polarizability through double quantum well structure with Dresselhaus spin-orbit coupling and applied oscillating fields. By the numerical calculations, it showed that spin-orbit coupling eliminated the spin degeneracy and led to the splitting of resonance peak. Electron tunneling through the broad potential well, transmission spectra were the symmetric Breit-Wigner resonance peaks, while through the narrow potential well, transmission spectra were the asymmetric Fano resonance peaks. The amplitude and the location of the resonance peaks would be controlled by the incoming energy and the width of the intermediate barrier. These interesting features might be used to devise tunable spin filters to realize the modulation of spin.