English

Feedback cooling a levitated nanoparticle's libration to below 100 phonons

Quantum Physics 2024-03-01 v1

Abstract

Macroscopic rotors are interesting model systems to test quantum theory and for quantum sensing. A promising approach for bringing these systems to the quantum regime is to combine sensitive detection with feedback cooling to reduce the thermal occupation of the mechanics. Here, we implement a backward-scattering scheme to efficiently detect all three libration modes of an optically levitated nanoparticle. We demonstrate parametric feedback cooling of all three libration degrees of freedom to below 16~mK, with one of the modes reaching the temperature of 1.3~mK, corresponding to a mean phonon number of 84. Finally, we characterize the backward-scattering scheme by determining its measurement efficiency to be 0.5\%.

Keywords

Cite

@article{arxiv.2402.19245,
  title  = {Feedback cooling a levitated nanoparticle's libration to below 100 phonons},
  author = {Jialiang Gao and Fons van der Laan and Joanna A. Zielinska and Andrei Militaru and Lukas Novotny and Martin Frimmer},
  journal= {arXiv preprint arXiv:2402.19245},
  year   = {2024}
}
R2 v1 2026-06-28T15:04:44.412Z