0533784 - ÚPT 2021 RIV US eng J - Journal Article
Arita, Y. - Simpson, Stephen Hugh - Zemánek, Pavel - Dholakia, K.
Coherent oscillations of a levitated birefringent microsphere in vacuum driven by nonconservative rotation-translation coupling.
Science Advances. Roč. 6, č. 23 (2020), č. článku eaaz9858. ISSN 2375-2548. E-ISSN 2375-2548
R&D Projects: GA ČR(CZ) GA19-17765S
Institutional support: RVO:68081731
Keywords : optical binding * force * dynamics * particle
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 14.143, year: 2020
Method of publishing: Open access
Result website:
https://advances.sciencemag.org/content/6/23/eaaz9858
DOI: https://doi.org/10.1126/sciadv.aaz9858

We demonstrate an effect whereby stochastic, thermal fluctuations combine with nonconservative optical forces to break detailed balance and produce increasingly coherent, apparently deterministic motion for a vacuum-trapped particle. The particle is birefringent and held in a linearly polarized Gaussian optical trap. It undergoes oscillations that grow rapidly in amplitude as the air pressure is reduced, seemingly in contradiction to the equipartition of energy. This behavior is reproduced in direct simulations and captured in a simplified analytical model, showing that the underlying mechanism involves nonsymmetric coupling between rotational and translational degrees of freedom. When parametrically driven, these self-sustained oscillators exhibit an ultranarrow linewidth of 2.2 mu Hz and an ultrahigh mechanical quality factor in excess of 2 x 10(8) at room temperature. Last, nonequilibrium motion is seen to be a generic feature of optical vacuum traps, arising for any system with symmetry lower than that of a perfect isotropic microsphere in a Gaussian trap.

Permanent Link: http://hdl.handle.net/11104/0312065