Widely tunable solid-state source of single-photons matching an atomic transition

Abstract

Hybrid quantum technologies aim to combine diverse quantum systems, mirroring classical computers' integration of electronic, photonic, magnetic, and mechanical components. Quantum dots in semiconductor nanowires emit high-purity, deterministic single photons with high repetition, while atomic ensembles offer photon storage and strong optical nonlinearities controllable by single photons. To interface quantum dots with atomic ensembles successfully, precise optical frequency matching of these two platforms is crucial. We demonstrate a simple, precise, reversible, broad-range, and local method for controlling the emission frequency of individual quantum dots embedded in tapered semiconductor nanowires. We then interface the quantum dots with an atomic ensemble via single-photons matched to hyperfine transitions and slow-light regions of the cesium D1-line. Our approach allows linking atomic and solid-state quantum systems and can potentially also be applied to other types of nanowire-embedded solid-state emitters, as well as for creating devices based on multiple solid-state emitters tuned to produce indistinguishable photons.