Transport signatures of Floquet Majorana fermions in driven topological superconductors

TL;DR

This paper investigates how Floquet Majorana fermions in driven topological superconductors produce distinctive, quantized conductance signatures in transport measurements, which are robust against weak disorder, providing a method for experimental identification.

Contribution

It introduces a quantized conductance sum rule as a signature of Floquet Majorana fermions and demonstrates its robustness against static disorder through analytical and numerical analysis.

Findings

Quantized conductance sum rule signals Floquet Majorana fermions

Sum rule remains robust under weak static disorder

Provides a practical method for experimental detection

Abstract

Floquet Majorana fermions are steady states of equal superposition of electrons and holes in a periodically driven superconductor. We study the experimental signatures of Floquet Majorana fermions in transport measurements and show, both analytically and numerically, that their presence is signaled by a quantized conductance sum rule over discrete values of lead bias differing by multiple absorption or emission energies at drive frequency. We also study the effects of static disorder and find that the quantized sum rule is robust against weak disorder. Thus, we offer a unique way to identify the topological signatures of Floquet Majorana fermions.