A proposal for time-dependent pure-spin-current generators
A proposal for time-dependent pure-spin-current generators
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DOI：
10.1063/1.4764557
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发表时间：
2012-11
影响因子：
4
通讯作者：
Y. S. Liu;Xi Yang;F. Chi;M. Si;Yong Guo
中科院分区：
文献类型：
--
作者：
Y. S. Liu;Xi Yang;F. Chi;M. Si;Yong Guo
我们提出了一种基于单能级量子点(QD)器件的纯自旋电流产生器。在低温强磁场下，与自旋相关的Seebeck系数在过渡区比稳态区迅速增大了几个数量级。这一事实归因于电子传输几率相对于量子点能级分裂的延迟效应。当在器件上施加温度梯度时，就会出现纯自旋电流。这一发现提出了一种增强热旋效应并通过含时外场产生纯自旋流的可行方法。
We propose a pure-spin-current generator based on a single level quantum dot (QD) device subjected to time-dependent magnetic fields. Under low temperature and high magnetic fields, the spin-dependent Seebeck coefficient in the transition regime is rapidly enhanced by several orders of magnitude larger than that in the steady regime. This fact is attributed to a delay effect of the electron transmission probability with respect to the split of the QD energy level. When a temperature gradient is applied across the device, the pure spin current emerges. The findings here suggest a feasible way of enhancing thermospin effects and generating the pure spin current by time-dependent external fields.