Non-equilibrium steady state of a driven levitated particle with feedback cooling

Author(s)
Jan Gieseler, Lukas Novotny, Clemens Moritz, Christoph Dellago
Abstract

Laser trapped nanoparticles have been recently used as model systems to study fundamental relations holding far from equilibrium. Here we study a nanoscale silica sphere levitated by a laser in a low density gas. The center of mass motion of the particle is subjected, at the same time, to feedback cooling and a parametric modulation driving the system into a non-equilibrium steady state. Based on the Langevin equation of motion of the particle, we derive an analytical expression for the energy distribution of this steady state showing that the average and variance of the energy distribution can be controlled separately by appropriate choice of the friction, cooling and modulation parameters. Energy distributions determined in computer simulations and measured in a laboratory experiment agree well with the analytical predictions. We analyze the particle motion also in terms of the quadratures and find thermal squeezing depending on the degree of detuning.

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Eidgenössische Technische Hochschule Zürich
Journal
New Journal of Physics
Volume
17
No. of pages
17
ISSN
1367-2630
DOI
https://doi.org/10.1088/1367-2630/17/4/045011
Publication date
04-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103036 Theoretical physics, 103015 Condensed matter, 103029 Statistical physics
Keywords
ASJC Scopus subject areas
General Physics and Astronomy
Portal url
https://ucrisportal.univie.ac.at/en/publications/53e46d90-8595-47e0-be38-0115e89373f5