Silicon optomechanical crystal resonator at millikelvin temperatures
Author(s): S. M. Meenehan, J.D. Cohen, S. Gröblacher, J. T. Hill, M. Aspelmeyer, O. Painter
Journal: Phys. Rev. A
DOI Number: 10.1103/PhysRevA.90.011803
Link: Link to publication
Optical measurements of a nanoscale silicon optomechanical crystal cavity with a mechanical resonance frequency of 3.6 GHz are performed at subkelvin temperatures. We infer optical-absorption-induced heating and damping of the mechanical resonator from measurements of phonon occupancy and motional sideband asymmetry. At the lowest probe power and lowest fridge temperature (Tf=10 mK), the localized mechanical resonance is found to couple at a rate of γi/2π=400 Hz (Qm=9×106) to a thermal bath of temperature Tb≈270 mK. These measurements indicate that silicon optomechanical crystals cooled to millikelvin temperatures should be suitable for a variety of experiments involving coherent coupling between photons and phonons at the single quanta level.