Abstract

During the 1990’s high-Q acoustic resonators coupled to high-Q electromagnetic resonator (or parametric) transducers were under development at the University of Western Australia for a variety of ultra-precise measurements. These systems relied on very low-noise pump oscillators and readout systems at microwave frequencies and produced the lowest noise resonant-bar gravitational wave detector of the decade. A research program to measure the Standard Quantum Limit (SQL) of displacement of an acoustic oscillator and perform Quantum Non-Demolition (QND) was initiated. Promising results were obtained using re-entrant cavities and Whispering Gallery modes in high-Q sapphire resonators. In the case of the sapphire transducer, operation in the resolved sideband cooling regime was achieved, which is a necessary requirement for QND measurement. In this presentation the major achievements of our parametric transducer work is summarized along with what is necessary to measure the SQL and perform a QND experiment using our technology.

© 2009 APS DLS