Transport properties of the Coulomb-Majorana junction

TL;DR

This paper presents a detailed theoretical analysis of quantum transport in Coulomb-Majorana junctions, revealing non-Fermi liquid behavior through conductance and noise characteristics influenced by Majorana states and Kondo physics.

Contribution

It introduces a comprehensive Keldysh phase action framework for nonequilibrium transport in Coulomb-Majorana systems, connecting them to a two-channel SO(M) Kondo model.

Findings

Transport exhibits non-Fermi liquid temperature and voltage dependence.

Majorana bound states significantly influence conductance and noise.

The model captures complex quantum correlations in multi-lead junctions.

Abstract

We provide a comprehensive theoretical description of low-energy quantum transport for a Coulomb-Majorana junction, where several helical Luttinger liquid nanowires are coupled to a joint mesoscopic superconductor with finite charging energy. Including the Majorana bound states formed near the ends of superconducting wire parts, we derive and analyze the Keldysh phase action describing nonequilibrium charge transport properties of the junction. The low-energy physics corresponds to a two-channel Kondo model with symmetry group SO(M), where M is the number of leads connected to the superconductor. Transport observables, such as the conductance tensor or current noise correlations, display non-trivial temperature or voltage dependences reflecting non-Fermi liquid behavior.