A strain-tunable quantum dot embedded in a nanowire antenna

TL;DR

This paper presents a quantum dot embedded in a nanowire antenna that can be strain-tuned to emit single photons with narrow spectral linewidths, promising for quantum technology applications.

Contribution

It introduces a strain-tunable quantum dot in a nanowire antenna with high spectral purity and demonstrates significant energy tuning despite nanowire relaxation effects.

Findings

Achieved up to 1.2 meV energy tuning of quantum dot emission

Produced single-photon emission with resolution-limited linewidths

Demonstrated strain-tunability in a nanowire-embedded quantum dot

Abstract

We demonstrate an elastically-tunable self-assembled quantum dot in a nanowire antenna that emits single photons with resolution-limited spectral linewidths. The single-photon device is comprised of a single quantum dot embedded in a top-down fabricated nanowire waveguide integrated onto a piezoelectric actuator. Non-resonant excitation leads to static (fluctuating) charges likely at the nanowire surface, causing DC Stark shifts (inhomogeneous broadening); for low excitation powers, the effects are not observed and resolution-limited linewidths are obtained. Despite significant strain-field relaxation in the high-aspect-ratio nanowires, we achieve up to 1.2 meV tuning of a dot's transition energy. Single-photon sources with high brightness, resolution-limited linewidths, and wavelength tunability are promising for future quantum technologies.