Spin-mechanical coupling of an InAs quantum dot embedded in a mechanical resonator

Coupling quantum systems to mechanical motion is of significant interest as a way of connecting disparate or distant quantum systems, for sensitive detection of motion, and for investigating the quantum limits of motion. Here we demonstrate the integration of InAs quantum dots with GaAs mechanical resonators and show significant strain-induced coupling between the quantum dot and mechanical motion. High resolution photoluminescence of a single quantum dot is measured synchronously with the driven mechanical resonator, showing significant strain induced shifts to the optical transitions of ~240 THz/strain. The effects on both the electron and hole Zeeman splittings are also determined by applying a magnetic field and taking the difference between photoluminescence lines. For an in-plane magnetic field, we measure negligible change in the electron Zeeman splitting but a large change in hole Zeeman splitting of ~7 THz/strain that varies from dot to dot according to the static Zeeman splitting. The large coupling of hole spins to strain is attributed to the stronger spin orbit interaction and the special role that spin orbit interaction plays for in-plane magnetic fields.