Cavity quantum electrodynamics with charge-controlled quantum dots coupled to a fiber Fabry-Perot cavity

TL;DR

This paper demonstrates the non-perturbative coupling of a charge-controlled quantum dot with a fiber-based microcavity, achieving the onset of strong coupling and advancing solid-state quantum interfaces.

Contribution

It introduces a method for deterministic charge control of quantum dots coupled to a fiber microcavity, enabling strong coupling conditions.

Findings

Coupling achieved with a cooperativity of 2

System at the onset of strong coupling

Advances towards high-efficiency spin-photon interfaces

Abstract

We demonstrate non-perturbative coupling between a single self-assembled InGaAs quantum dot and an external fiber-mirror based microcavity. Our results extend the previous realizations of tunable microcavities while ensuring spatial and spectral overlap between the cavity-mode and the emitter by simultaneously allowing for deterministic charge control of the quantum dots. Using resonant spectroscopy, we show that the coupled quantum dot cavity system is at the onset of strong coupling, with a cooperativity parameter of 2. Our results constitute a milestone towards the realization of a high efficiency solid-state spin-photon interface.