振荡磁场量子点中自旋流的交流响应(英文)

Alternating response of spin current in a magnetic-oscillating quantum dot

我们在联合到一个正常金属电极的一个量点系统调查旋转电流的轮流出现的反应，到哪个一轮流出现驾驶电压并且抽旋转磁场被使用。平均时间的旋转电流的表示并且它的微分基于一个非平衡格林鈥檚 功能方法被获得。我们发现为给定的旋转频率，旋转电流很快增加并且当驾驶频率增加时，看起来有小步。当驾驶频率进一步正在增加，旋转电流能显著地被提高并且来临稳定的价值。帮助光子的过程引起旋转电流的有趣的特征。旋转电流上的门电压和温度的影响详细被检验。

We investigate alternating response of the spin current in a quantum dot system coupled to a normal metal electrode, to which an alternating driving voltage and a pumping rotating magnetic field are applied. The expression of the time-averaged spin current and its differential is obtained based on a non-equilibrium Green＇s function method. We find that for a given rotating frequency, the spin current increases rapidly and appears to have small steps when the driven frequency increases. As the driven frequency is further increasing, the spin current can be significantly enhanced and approaches a stable value. The photon-assisted processes bring about interesting features of spin current. The influence of the gate voltage and temperature on the spin current is examined in detail.