Signature of snaking states in the conductance of core-shell nanowires

TL;DR

This paper models core-shell nanowires as cylindrical surfaces under magnetic fields, revealing that snaking electron states significantly influence conductance, which can be modulated by electric fields and contact positioning.

Contribution

It introduces a detailed model of snaking states in core-shell nanowires and predicts their impact on conductance, including peak splitting and dependence on contact placement.

Findings

Snaking states dominate low-energy conductance peaks.

Transverse electric fields can split conductance peaks.

Contact placement affects the conductance peak amplitudes.

Abstract

We model a core-shell nanowire (CSN) by a cylindrical surface of finite length. A uniform magnetic field perpendicular to the axis of the cylinder forms electron states along the lines of zero radial field projection, which can classically be described as snaking states. In a strong field, these states converge pairwise to quasidegenerate levels, which are situated at the bottom of the energy spectrum. We calculate the conductance of the CSN by coupling it to leads, and predict that the snaking states govern transport at low chemical potential, forming isolated peaks, each of which may be split in two by applying a transverse electric field. If the contacts with the leads do not completely surround the CSN, as is usually the case in experiments, the amplitude of the snaking peaks changes when the magnetic field is rotated, determined by the overlap of the contacts with the snaking states.