Tuning of quantum dots in micropillar cavities for hybrid photonic interfaces

Hybrid quantum interfaces that combine the fast, deterministic single-photon emission of semiconductor quantum dots (QDs) with the long-lived quantum memories of atomic vapors represent a promising route towards scalable quantum networks and distributed quantum computing. However, the realization of such interfaces is fundamentally limited by the stringent spectral matching required between the narrow optical transitions of atomic systems and the intrinsically variable emission of QDs. Moreover, achieving bright QD emission requires integration into an efficient light-collecting structure. In this work, we present a systematic investigation of three tuning mechanisms for cavity-enhanced QDs embedded in micropillar cavities: thermal tuning, in situ laser processing, and nitrogen gas deposition. We experimentally evaluated the applicability of each method and characterized their tuning ranges and precisions. All three methods enable reliable and precise wavelength shifts, even for QDs in larger micropillars. These results provide practical strategies for achieving spectral resonance between QD emitters and atomic vapor lines, paving the way for tunable solid-state-atomic hybrid platforms for photon storage, synchronization, and interfacing in hybrid quantum systems.