Photothermal effects in ultra-precisely stabilized tunable microcavities
Abstract
We study the mechanical stability of a tunable high-finesse microcavity under ambient conditions and investigate light-induced effects that can both suppress and excite mechanical fluctuations. As an enabling step, we demonstrate the ultra-precise electronic stabilization of a microcavity. We then show that photothermal mirror expansion can provide high-bandwidth feedback and improve cavity stability by almost two orders of magnitude. At high intracavity power, we observe self-oscillations of mechanical resonances of the cavity. We explain the observations by a dynamic photothermal instability, leading to parametric driving of mechanical motion. For an optimized combination of electronic and photothermal stabilization, we achieve a feedback bandwidth of kHz and a noise level of m rms.
Cite
@article{arxiv.1609.00698,
title = {Photothermal effects in ultra-precisely stabilized tunable microcavities},
author = {Johannes F. S. Brachmann and Hanno Kaupp and Theodor W. Hänsch and David Hunger},
journal= {arXiv preprint arXiv:1609.00698},
year = {2016}
}