Majorana bound state in the continuum and Fano effect formed by the coupling of two Andreev-reflection channels

Abstract

Majorana-induced Andreev reflection (AR) is theoretically investigated by considering the interplay between two AR channels, each of which is formed by the lead and its coupled topological-superconducting nanowire with Majorana bound states. By means of the Scattering matrix and nonequilibirum Green’s function technique, relevant observables are analyzed, including the differential conductance, the density of states, and shot-noise Fano factors. It is found that Majorana bound states in the continuum (MBIC) can be constructed, under the condition of two uniform nanowires and inter-channel couplings. Otherwise, the Fano effect is allowed to occur, which is manifested as the appearance of additional conductance dips. In particular, the Fano antiresonance can be induced by constructing the identical inter-channel couplings. All these results can be helpful in understanding the MBIC contributed by the Majorana-assisted ARs.

Keywords

• Majorana bound state in the continuum
• Fano effect
• Andreev reflection
• Nonequilibirum Green’s function