We measure the frequency dependence of the mechanical quality factor (Q) of SiN membrane oscillators and observe a resonant variation of Q by more than two orders of magnitude. The frequency of the fundamental mechanical mode is tuned reversibly by up to 40% through local heating with a laser. Several distinct resonances in Q are observed that can be explained by coupling to membrane frame modes. Away from the resonances, the background Q is independent of frequency and temperature in the measured range.
@article{arxiv.1108.2617,
title = {Spectroscopy of mechanical dissipation in micro-mechanical membranes},
author = {Andreas Jöckel and Matthew T. Rakher and Maria Korppi and Stephan Camerer and David Hunger and Matthias Mader and Philipp Treutlein},
journal= {arXiv preprint arXiv:1108.2617},
year = {2011}
}