正常金属/量子点/超导结构可以产生Andreev反射现象,如果在量子点上耦合Majorana束缚态(MBSs),其Andreev反射电导将发生特殊的变化,因而可用于探测MBSs.研究了MBSs对连接在正常金属和超导体之间的线型三量子点输运性质的影响,发现零费米能处的Andreev反射电导在不考虑MBSs之间的耦合时始终等于0.5G0(G0=2e2/h),不受量子点能级、量子点间耦合强度、量子点与电极之间耦合强度的影响,具有明显的鲁棒性.
Andreev reflection can occur in normal metal/quantum dots/superconductor structures. If the Majorana bound states(MBSs)are coupled to the quantum dots of the structure, the Andreev reflected conductance will change in a special way and can be used to detect MBSs.In this paper, the effect of MBSs on the transport properties of linear triple quantum dots connected between normal metal and superconductor is studied.It is found that the Andreev reflection conductance at zero Fermi energy is always equal to 0.5 G0(G0=2e2/h)without considering the coupling between MBSs. And it is not affected by the quantum dot energy level, the coupling strength between quantum dots, and the coupling strength between quantum dots and electrodes, and it has obvious robustness.
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