Fano effect in the Andreev reflection of the Aharonov–Bohm–Fano ring with Majorana bound states

• The Fano effect is determined by dot level, dot-MBS coupling, and dot-MBS and MBS-lead couplings.
• We analyze the Fano effect by transforming the ring into its Nambu representation.
• Results are helpful for understanding the MBS-assisted Andreev reflection.

The Andreev reflection in an Aharonov–Bohm–Fano ring induced by Majorana bound states (MBSs) is theoretically investigated. We find that compared with the Fano effect in the normal electron tunneling process, the Fano effect here is more determined by the structural parameters, i.e., the quantum dot level, the dot-MBS coupling, and the dot-MBS and MBS-lead couplings. By transforming the ring into its Nambu representation, we present a comprehensive analysis about the quantum interference in the Andreev reflection, and then explain the reason for the occurrence of the Fano effect. These results will be helpful for understanding the quantum interference in the MBS-assisted Andreev reflection.