Transport through Andreev bound states in a Weyl semimetal quantum dot

TL;DR

This paper investigates electron transport in a Weyl semimetal quantum dot connected to a superconductor and a normal lead, revealing universal conductance features influenced by Klein tunneling and chiral excitations.

Contribution

It introduces a combined scattering matrix and lattice simulation approach to analyze conductance in Weyl semimetal quantum dots, highlighting universal behaviors and experimental observability.

Findings

Conductance peaks occur at regular intervals with double periodicity.

Two characteristic frequencies influence conductance: Klein tunneling and chirality.

Universal conductance features are demonstrated through simulations.

Abstract

We study transport through a Weyl semimetal quantum dot sandwiched between an $s$-wave superconductor and a normal lead. The conductance peaks at regular intervals and exhibits double periodicity with respect to two characteristic frequencies of the system, one that originates from Klein tunneling in the system and the other coming from the chiral nature of the excitations. Using a scattering matrix approach as well as a lattice simulation, we demonstrate the universal features of the conductance through the system and discuss the feasibility of observing them in experiments.