Properties of dissipative Floquet Majorana modes using a quantum dot

TL;DR

This paper investigates the conductance properties of dissipative Floquet Majorana zero modes in a driven nanowire coupled to a quantum dot, highlighting how their lifetime affects measurable conductance and proposing a method to test their presence.

Contribution

It introduces a numerical approach to accurately account for dissipation effects on Floquet Majorana modes and relates their lifetime to observable conductance signatures.

Findings

Conductance approaches e^2/2h for long FMZM lifetime

Conductance approaches e^2/h as FMZM lifetime decreases

Method can test FMZM presence and lifetime in devices

Abstract

We study the electronic conductance of dissipative Floquet Majorana zero modes (FMZMs) in a periodically driven nanowire coupled to a quantum dot. We use a numerical method which can accurately take into account the dissipation effects from the superconducting bath, which causes the FMZMs to have a finite lifetime. Our results show that, in the weak nanowire-dot coupling regime, the peak conductance at zero temperature of the resonant dot can be well approximated by a universal function of the FMZM lifetime rescaled with the nanowire-dot coupling strength: For a long FMZM's lifetime, the conductance approaches the characteristic quantized value of $G = e^2/2h$, whereas $G \rightarrow e^2/h$ (uncoupled dot) as the FMZMs' lifetime goes to zero. In principle, our method can be used to test the presence and lifetime of FMZMs in such devices, which is key for any practical application of these topological states.