Electric and Magnetic Field-dependent Tunneling between Coupled Nanowires

TL;DR

This theoretical study explores how external electric and magnetic fields influence electron transport in coupled nanowires, revealing a field-induced metal-insulator transition and conductance features relevant to experimental observations.

Contribution

The paper introduces a minimal theoretical model predicting field-dependent transport phenomena, including a metal-insulator transition, in coupled nanowire systems, aligning with experimental data.

Findings

Magnetic field induces a metal-insulator transition.

External potential bias affects conductance features.

Predictions match experimental transport measurements.

Abstract

Coupled quasi-one-dimensional (quasi-1D) electron systems host rich emergent physics that cannot be accounted for by understanding isolated 1D electron systems alone. Open questions remain about how transport in these arrays can be manipulated by the application of external electric and magnetic fields. In this theoretical study, we consider a pair of coupled nanowires with non-interacting electrons. We find that a metal-insulator transition is induced by an out-of-plane magnetic field and a transverse potential bias on an array of such coupled wires. We demonstrate the existence of distinct conductance features and highlight the crucial role played by the field dependence of the interwire potential barrier on transport properties. These predictions agree well with transport experiments performed on coupled nanowires sketched on an LaAlO3/SrTiO3 interface. Since our model makes minimal assumptions, we expect our predictions to hold for a wide class of coupled 1D systems.