三终端多臂量子环中的持续电流

本文提出了三终端多臂量子环模型，并采用特殊方法来计算持续电流，研究发现：总磁通为零时，持续电流随半导体环增大做非周期和不等幅的振荡.总磁通不为零时，持续电流随AB磁通增强做周期性等幅振荡，Rashba自旋轨道耦合具有改变两种持续电流位相和位相差的效应. 平均持续电流的大小与各臂的臂长和所处的位置以及磁通分布相关.AB磁通对两种持续电流具有不同影响，两种持续电流是可分离的.

Persistent spin currents in a triple-terminal quantum ring with three arms

A new model of a triple-terminal quantum ring with three arms is proposed. We develop an equivalent method for reducing the triple-terminal quantum ring to the double-terminal quantum ring and calculate the persistent spin currents in this model. The results indicate that the persistent spin currents show behavior of nonperiodic and unequal amplitude oscillation with increasing semiconductor ring size when the total magnetic flux is zero. However, when the total magnetic flux is non-zero, the persistent spin currents make periodic equal amplitude oscillations with increasing AB magnetic flux intensity. At the same time, the two kinds of spin state persistent spin currents have the same frequency and amplitude but the inverse phase. In addition, the Rashba spin-orbit interaction affects the phase and the phase difference of the persistent spin currents. The average persistent spin currents relate to the arm length and the terminal position as well as the distribution of the magnetic flux in each arm. Furthermore, our results indicate that the AB magnetic flux has different influences on the two kinds of spin state electrons.