Controlled Wavefunction Mixing in a Strongly Coupled One-Dimensional Wire

TL;DR

This study explores how strong coupling and magnetic fields influence wavefunction mixing and transport in two closely spaced one-dimensional quantum wires, revealing tunable inter-wire interactions and energy gap behaviors.

Contribution

It demonstrates controlled wavefunction mixing in strongly coupled 1D wires and how magnetic fields modulate their coupling and energy gaps.

Findings

Resonance conditions produce symmetric and antisymmetric subbands with larger energy gaps than 2D systems.

Magnetic fields enhance wavefunction mixing at low fields.

High magnetic fields decouple the wires completely.

Abstract

We investigate the transport properties of two strongly coupled ballistic one-dimensional (1D) wires, defined by a split-gate structure deposited on a GaAs/AlGaAs double quantum well. Matching the widths and electron densities of the two wires brings them into resonance, forming symmetric and antisymmetric 1D subbands separated by energy gaps that are measured to be larger than their two-dimensional counterpart. Applying a magnetic field parallel to the wire axes enhances wavefunction mixing at low fields, whereas at high fields the wires become completely decoupled.