Quantum interference in nanometric devices: ballistic transport across arrays of T-shaped quantum wires

TL;DR

This paper investigates quantum interference effects in T-shaped semiconductor quantum wires, demonstrating how conductance can be controlled by device geometry and exploring potential for spin-dependent transport in nanoscale devices.

Contribution

It introduces a method to analyze ballistic transport in T-shaped quantum wires using scattering matrix and Landauer-Büttiker theory, highlighting tunable conductance profiles and spin-dependent effects.

Findings

Conductance profiles depend on quantum well widths and wire configurations.

Different device geometries enable control over quantum interference effects.

Potential for spin-dependent conductance in hole-based T-wires.

Abstract

We propose that the recently realized T-shaped semiconductor quantum wires (T-wires) could be exploited as three-terminal quantum interference devices. T-wires are formed by intersecting two quantum wells (QWs). By use of a scattering matrix approach and the Landauer-B\"uttiker theory, we calculate the conductance for ballistic transport in the parent QWs and across the wire region as a function of the injection energy. We show that different conductance profiles can be selected by tailoring the widths of the QWs and/or combining more wires on the scale of the Fermi wavelength. Finally, we discuss the possibility of obtaining spin-dependent conductance of ballistic holes in the same structures.