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arXiv · 2503.01014

Controlling emitter-field coupling in waveguides with a nanomechanical phase shifter

Celeste Qvotrup·Ying Wang·Marcus Albrechtsen·Rodrigo A. Thomas·Zhe Liu·Sven Scholz·Arne Ludwig·Leonardo Midolo
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Abstract

The ability to control light-matter interfaces with solid-state photon emitters is a major requirement for the development of quantum photonic integrated circuits. We demonstrate controllable coupling between a quantum dot and an optical mode in a dielectric waveguide using a nano-opto-electro-mechanical phase shifter and a photonic crystal mirror. By controlling the phase, we induce a virtual displacement of the mirror that modifies the local density of states at the position of the emitter, thereby enhancing or suppressing spontaneous emission without an optical cavity. We observe a broadband tuning of the spontaneous emission rate and a modulation of the intensity emitted by the quantum dot in the waveguide. The method reported here could be employed to optimize the emitter-field interaction between quantum dots in-operando, by maximizing a single-photon source generation rate or adjusting its lifetime, as well as a characterization tool for the direct measurement of emitter-photon cooperativity.

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Celeste Qvotrup, Ying Wang, Marcus Albrechtsen, Rodrigo A. Thomas, Zhe Liu, Sven Scholz, Arne Ludwig, Leonardo Midolo. 2025-03-02. Controlling emitter-field coupling in waveguides with a nanomechanical phase shifter. https://arxiv.org/abs/2503.01014

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