2013/09/20 by Dac Trung Nguyen, Christophe Baker, William Hease +6 · 1 citation
Physics and Astronomy · #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1063/1.4846515
4 pages, 1 table, 3 figures
arxiv created 2013/09/20 · arxiv updated 2015/06/17
We report on optomechanical GaAs disk resonators with ultrahigh quality factor - frequency product Qf. Disks standing on a simple pedestal exhibit GHz breathing modes attaining a Qf of 1013 measured under vacuum at cryogenic temperature. Clamping losses are found to be the dominant source of dissipation in this configuration. A new type of disk resonator integrating a shield within the pedestal is then proposed and its working principles and performances investigated by numerical simulations. For dimensions compatible with fabrication constraints, the clamping-loss-limited Q reaches 107-109 corresponding to Qf of 1016-1018. This shielded pedestal approach applies to any heterostructure presenting an acoustic mismatch.