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arXiv · 2402.08179

Near-field optomechanical transduction enhanced by Raman gain

Ryoko Sakuma·Motoki Asano·Hiroshi Yamaguchi·Hajime Okamoto
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Abstract

Raman-gain-enhanced near-field optomechanical transduction between a movable optical cavity and SiN-membrane resonator is demonstrated. The Raman gain compensates for the intrinsic loss of the cavity and amplifies the optomechanical transduction, through which the membrane vibration is sensed using a high-Q whispering-gallery-mode optical cavity evanescently. The optical Q of the cavity resonance is improved with respect to the optical pump power, which results in an increase in the optomechanically transduced vibration signals of the mechanical resonator. Our near-field optomechanical coupling approach with optical gain realizes highly sensitive displacement measurement in nano- and micro-mechanical resonators consisting of arbitrary materials and structures.

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Ryoko Sakuma, Motoki Asano, Hiroshi Yamaguchi, Hajime Okamoto. 2024-02-13. Near-field optomechanical transduction enhanced by Raman gain. https://arxiv.org/abs/2402.08179

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