Modulated nonlocality of Majorana bound states due to the presence of PT-symmetric quasiparticle poisoning

Abstract

By considering one topological superconducting nanowire to be coupled to the metallic leads in a parallel way, we investigate the nonlocality of the Majorana bound states (MBSs) characterized by the zero-bias conductance peak. It is shown that $\mathrm{PT}$-symmetric quasiparticle poisoning can annihilate the Majorana nonlocality by quenching its-induced zero-bias conductance peak. However, when the Majorana nonlocality is destroyed by the nonzero inter-MBS coupling, this quasiparticle poisoning can relieve the zero-bias conductance dip. What is notable is that as the quasiparticle poisoning reaches its exceptional point, the nonlocality of MBSs can be restored, manifested as the appearance of zero-bias conductance peak. We believe that our findings are helpful for understanding the MBS properties with $\mathrm{PT}$-symmetric quasiparticle poisoning.