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arXiv · 2104.11648

Laser cooling of a Planck mass object close to the quantum ground state

Leonhard Neuhaus·Remi Metzdorff·Salim Zerkani·Sheon Chua·Jean Teissier·Daniel Garcia-Sanchez·Samuel Deleglise·Thibaut Jacqmin·Tristan Briant·Jerome Degallaix·Vincent Dolique·Geppo Cagnoli·Olivier Le Traon·Claude Chartier·Antoine Heidmann·Pierre-Francois Cohadon
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Abstract

Quantum mechanics has so far not been tested for mechanical objects at the scale of the Planck mass $\sqrt{\hbar c/ G} \simeq 22\,\mu\mathrm{g}$. We present an experiment where a 1 mm quartz micropillar resonating at 3.6 MHz with an effective mass of 30 $\mu$g is cooled to 500 mK with a dilution refrigerator, and further optomechanically sideband-cooled to an effective temperature of 3 mK, corresponding to a mode thermal occupancy of 20 phonons. This nearly 1000-fold increase in the mass of an optomechanical system with respect to previous experiments near the quantum ground state opens new perspectives in the exploration of the quantum/classical border.

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Leonhard Neuhaus, Remi Metzdorff, Salim Zerkani, Sheon Chua, Jean Teissier, Daniel Garcia-Sanchez, Samuel Deleglise, Thibaut Jacqmin, Tristan Briant, Jerome Degallaix, Vincent Dolique, Geppo Cagnoli, Olivier Le Traon, Claude Chartier, Antoine Heidmann, Pierre-Francois Cohadon. 2021-04-23. Laser cooling of a Planck mass object close to the quantum ground state. https://arxiv.org/abs/2104.11648

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