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arXiv · 2301.10554

Optomechanical feedback cooling of a 5 mm-long torsional mode

Dianqiang Su·Yuan Jiang·Pablo Solano·Luis A. Orozco·John Lawall·Yanting Zhao
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Abstract

We report three orders of magnitude optical cooling of the fundamental torsional mode of a 5 mm-long, 550 nm diameter optical nanofiber. The rotation of the nanofiber couples to the polarization of guided laser fields. We use a weak laser probe to monitor the rotation, and use feedback to modulate the polarization of an auxiliary drive laser providing torque. Our results present a tool for the optomechanical control of large-scale torsional resonators, with metrological applications and potential implications for studying macroscopic objects in quantum states.

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Dianqiang Su, Yuan Jiang, Pablo Solano, Luis A. Orozco, John Lawall, Yanting Zhao. 2023-01-25. Optomechanical feedback cooling of a 5 mm-long torsional mode. https://arxiv.org/abs/2301.10554

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