Half-integer quantized charge pumping induced by a Majorana fermion

Abstract

We investigate the adiabatic topological charge pumping in a topological superconductor utilizing a quantum anomalous Hall insulator proximity coupled to an $s$-wave superconductor. We show that topological pumping is characterized by the appearance of protected Majorana edge states during the course of a pumping cycle. In a topological superconductor with a single Majorana edge state, the Majorana state will be pushed into the electrode in a cycle. This leads to a half-integer quantized pumped charge, because a Majorana fermion can be viewed as half of a fermion. The half-integer quantized charge pumping would serve as a fingerprint of a Majorana fermion.