Effect of Majorana bound states on transport properties of normal metal/triple quantum dots/superconductor structure

doi:10.3969/j.issn.1000-1565.2020.05.005

Abstract

Abstract: 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.

Key words: Majorana bound states, triple quantum dots, Andreev reflection

CLC Number:

QIN Fang,SUN Yanxiu,WANG Suxin. Effect of Majorana bound states on transport properties of normal metal/triple quantum dots/superconductor structure[J]. Journal of Hebei University (Natural Science Edition), 2020, 40(5): 477-483.

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