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arXiv · 2408.13405

Ultracoherent GHz Diamond Spin-Mechanical Lamb Wave Resonators

Xinzhu Li·Ignas Lekavicius·Jens Noeckel·Hailin Wang
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Abstract

We report the development of an all-optical approach that excites the fundamental compression mode in a diamond Lamb wave resonator with an optical gradient force and detects the induced vibrations via strain coupling to a silicon vacancy center, specifically, via phonon sidebands in the optical excitation spectrum of the silicon vacancy. Sideband optical interferometry has also been used for the detection of the in-plane mechanical vibrations, for which conventional optical interferometry is not effective. These experiments demonstrate a GHz fundamental compression mode with a Q-factor >10^7 at temperatures near 7 K, providing a promising platform for reaching the quantum regime of spin mechanics, especially phononic cavity QED of electron spins.

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Xinzhu Li, Ignas Lekavicius, Jens Noeckel, Hailin Wang. 2024-08-23. Ultracoherent GHz Diamond Spin-Mechanical Lamb Wave Resonators. https://doi.org/10.1021/acs.nanolett.4c03071

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