Photoconductive gain in semiconductor quantum wires

TL;DR

This paper demonstrates photoconductive gain in AlGaAs/GaAs quantum wires, revealing subband structures through photoresponse and showing the effect persists up to 17 Kelvin, advancing understanding of optoelectronic properties in low-dimensional systems.

Contribution

It introduces a method to observe subband structures in quantum wires via photoconductive gain, with temperature stability up to 17 Kelvin.

Findings

Subband maxima are visible in photoresponse measurements.

Photoconductive gain persists up to 17 Kelvin.

Optically induced holes shift subbands in quantum wires.

Abstract

We report on a photoconductive gain in semiconductor quantum wires which are lithographically defined in an AlGaAs/GaAs quantum well via a shallow-etch technique. The effect allows resolving the one-dimensional subbands of the quantum wires as maxima in the photoresponse across the quantum wires. We interpret the results by optically induced holes in the valence band of the quantum well which shift the one-dimensional subbands of the quantum wire. Here we demonstrate that the effect persists up to a temperature of about 17 Kelvin.