Scheme to measure Majorana fermion lifetimes using a quantum dot

TL;DR

This paper proposes an experimental setup using a quantum dot to measure the parity lifetime of Majorana bound states, which is crucial for their application in topological quantum computing.

Contribution

It introduces a novel method to directly measure Majorana parity lifetime through non-linear transport spectroscopy involving a quantum dot.

Findings

Parity relaxation affects the non-linear transport spectrum.

Strong overlap of Majorana fermions increases the current peak height.

The lifetime can be inferred from the peak height in the spectrum.

Abstract

We propose a setup to measure the lifetime of the parity of a pair of Majorana bound states. The proposed experiment has one edge Majorana state tunnel coupled to a quantum dot, which in turn is coupled to a metallic electrode. When the Majorana Fermions overlap, even a small relaxation rate qualitatively changes the non-linear transport spectrum, and for strong overlap the lifetime can be read off directly from the height of a current peak. This is important for the usage of Majorana Fermions as a platform for topological quantum computing, where the parity relaxation is a limiting factor.