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arXiv · 2412.14117

High-purity quantum optomechanics at room temperature

Lorenzo Dania·Oscar Schmitt Kremer·Johannes Piotrowski·Davide Candoli·Jayadev Vijayan·Oriol Romero-Isart·Carlos Gonzalez-Ballestero·Lukas Novotny·Martin Frimmer
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Abstract

Exploiting quantum effects of mechanical motion, such as backaction evading measurements or squeezing, requires preparation of the oscillator in a high-purity state. The largest state purities in optomechanics to date have relied on cryogenic cooling, combined with coupling to electromagnetic resonators driven with a coherent radiation field. In this work, we cool the mega-hertz-frequency librational mode of an optically levitated silica nanoparticle from room temperature to its quantum ground state. Cooling is realized by coherent scattering into a Fabry-Perot cavity. We use sideband thermometry to infer a phonon population of 0.04 quanta under optimal conditions, corresponding to a state purity of 92%. The purity reached by our room-temperature experiment exceeds the performance offered by mechanically clamped oscillators in a cryogenic environment. Our work establishes a platform for high-purity quantum optomechanics at room temperature.

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Lorenzo Dania, Oscar Schmitt Kremer, Johannes Piotrowski, Davide Candoli, Jayadev Vijayan, Oriol Romero-Isart, Carlos Gonzalez-Ballestero, Lukas Novotny, Martin Frimmer. 2024-12-18. High-purity quantum optomechanics at room temperature. https://arxiv.org/abs/2412.14117

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