We present a study of three-mode parametric instability in large-scale gravitational-wave detectors. Previous work used a linearised model to study the onset of instability. This paper presents a non-linear study of this phenomenon, which shows that the initial stage of exponential rise of the amplitudes of a higher order optical mode and the mechanical internal mode of the mirror is followed by a saturation phase, in which all three participating modes reach a new equilibrium state with constant oscillation amplitudes. Results suggest that stable operation of interferometers may be possible in the presence of such instabilities, thereby simplifying the task of suppression.
@article{arxiv.1409.3284,
title = {Time evolution of parametric instability in large-scale gravitational-wave interferometers},
author = {Stefan L. Danilishin and Sergey P. Vyatchanin and David G. Blair and Ju Li and Chunnong Zhao},
journal= {arXiv preprint arXiv:1409.3284},
year = {2015}
}
Comments
11 pages, 7 figures.Version 3 features added fig. 4 and refined discussion on non-linear input-output relations for 3-mode parametric system above the threshold, given in Sec. V