Nonlocality of Majorana modes in hybrid nanowires

Abstract

The nonlocal character of Majorana zero modes is a key feature for topological protection of Majorana qubits, and distinguishes separated Majorana bound states from localized Andreev modes. Applying recent theoretical results on the coupling of quantum dots at the wire ends to the zero-energy mode in the wire, the authors provide a first quantitative measure of the nonlocality of Majorana modes in semiconductor-superconductor hybrid nanowires. The spin character of the Majorana mode is revealed by analyzing its coupling to two consecutive quantum dot resonances. Cases of zero modes with moderate and high degrees of nonlocality are compared.