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We present first results from a number of experiments conducted on a 0.53 kgcylindrical dumbbell-shaped sapphire crystal. This is the first reportedoptomechanical experiment of this nature utilising a novel modification to thetypical cylindrical architecture. Mechanical motion of the crystal structurealters the dimensions of the crystal, and the induced strain changes thepermittivity. These two effects result in parametric frequency modulation ofresonant microwave whispering gallery modes that are simultaneously excitedwithin the crystal. A novel low-noise microwave readout system is implementedallowing extremely low noise measurements of this frequency modulation near ourmodes of interest, having a phase noise floor of -165 dBc/Hz at 100 kHz.Fine-tuning of the crystal's suspension has allowed for the optimisation ofmechanical quality factors in preparation for cryogenic experiments, with avalue of Q=8 x 10^7 achieved at 127 kHz. This results in a Q x f product of10^13, equivalent to the best measured values in a macroscopic sapphiremechanical system. Results are presented that demonstrate the excitation ofmechanical modes via radiation pressure force, allowing an experimental methodof determining the transducer's displacement sensitivity df/dx, and calibratingthe system. Finally, we demonstrate parametric back-action phenomenon withinthe system. These are all important steps towards the overall goal of theexperiment; to cool a macroscopic device to the quantum ground state atmillikelvin temperatures.

Precision Measurement of a low-loss Cylindrical Dumbbell-Shaped Sapphire Mechanical Oscillator using Radiation Pressure