Quantum dot opto-mechanics in a fully self-assembled nanowire

TL;DR

This paper demonstrates that quantum dots embedded in self-assembled nanowires can be coupled to mechanical motion, enabling tunable interactions and potential quantum control without external fields.

Contribution

It introduces a fully self-assembled quantum dot nanowire system where opto-mechanical coupling is intrinsic and tunable, advancing quantum nanomechanics.

Findings

Quantum dots modulate emission energy via nanowire oscillations.

Mechanical motion enables tuning of quantum dot resonance.

Intrinsic strain-based coupling allows quantum control without external fields.

Abstract

We show that fully self-assembled optically-active quantum dots (QDs) embedded in MBE-grown GaAs/AlGaAs core-shell nanowires (NWs) are coupled to the NW mechanical motion. Oscillations of the NW modulate the QD emission energy in a broad range exceeding 14 meV. Furthermore, this opto-mechanical interaction enables the dynamical tuning of two neighboring QDs into resonance, possibly allowing for emitter-emitter coupling. Both the QDs and the coupling mechanism -- material strain -- are intrinsic to the NW structure and do not depend on any functionalization or external field. Such systems open up the prospect of using QDs to probe and control the mechanical state of a NW, or conversely of making a quantum non-demolition readout of a QD state through a position measurement.