Cold damping of levitated optically coupled nanoparticles

0579379 - ÚPT 2024 RIV US eng J - Journal Article
Liška, Vojtěch - Zemánková, Tereza - Svak, Vojtěch - Jákl, Petr - Ježek, Jan - Bránecký, Martin - Simpson, Stephen Hugh - Zemánek, Pavel - Brzobohatý, Oto
Cold damping of levitated optically coupled nanoparticles.
Optica. Roč. 10, č. 9 (2023), s. 1203-1209. ISSN 2334-2536. E-ISSN 2334-2536
R&D Projects: GA ČR(CZ) GF21-19245K; GA MŠMT(CZ) EF16_026/0008460
Grant - others:AV ČR(CZ) AP2002
Program: Akademická prémie - Praemium Academiae
Institutional support: RVO:68081731
Keywords : optical binding * nanoparticles * optical levitation
OECD category: Optics (including laser optics and quantum optics)
Impact factor: 10.4, year: 2022
Method of publishing: Open access
https://opg.optica.org/optica/fulltext.cfm?uri=optica-10-9-1203&id=537233

Methods for controlling the motion of single particles, optically levitated in vacuum, have developed rapidly in recent years. The technique of cold damping makes use of feedback-controlled, electrostatic forces to increase dissipation without introducing additional thermal fluctuations. This process has been instrumental in the ground-state cooling of individual electrically charged nanoparticles. Here we show that the same method can be applied to a pair of nanoparticles, coupled by optical binding forces. These optical binding forces are about three orders of magnitude stronger than typical Coulombic inter-particle force and result in a coupled motion of both nanoparticles characterized by a pair of normal modes. We demonstrate cold damping of these normal modes, either independently or simultaneously, to sub-Kelvin temperatures at pressures of 5 × 10−3 mbar. Experimental observations are captured by a theoretical model that we use to survey the parameter space more widely and to quantify the limits imposed by measurement noise and time delays. Our work paves the way for the study of quantum interactions between meso-scale particles and the exploration of multiparticle entanglement in levitated optomechanical systems.
Permanent Link: https://hdl.handle.net/11104/0348207