There is considerable gravity oriented material on the Web. The few odd bits sampled below are similar in spirit to our approach.
=============== http://www.pd.uwa.edu.au/Grav_Wave/AdvResMass.html ADVANCED RESONANT-MASS GRAVITATIONAL WAVE DETECTORS APPROACHING QUANTUM LIMITED SENSITIVITY Michael .E. Tobar Australian International Gravitational Research Centre, Dept. of Physics, University of Western Australia, Perth, 6907, Australia A large improvement is envisaged for the University of Western Australia's (UWA) resonant-mass Gravitational Wave (GW) detector due to a new type of parametric transducer constructed from low-loss monocrystalline sapphire. Single pieces of crystals can be used as both the resonant microwave transducer and a tuned resonant mechanical mass. The sensitivity is determined by the acoustic losses in the detector as well as the phase noise of the pump oscillator driving the transducer. Newly developed cryogenic microwave oscillators are now available with ultra-low noise levels of -165 dBc/Hz [1]. We project that this can be further reduced to -185 dBc/Hz with the advent of recent technology. Calculations suggest by implementing this technology the noise temperature can be reduced from a few mK to the order of micro Kelvin in a liquid helium cryostat. This sensitivity can be achieved in the short term with very little expense in comparison to the construction of an interferometer, and is ideal for correlation experiments with the proposed AIGO interferometer. Cryogenic sapphire transducer technology presents a viable alternative to SQUID technology. The quantum limit of a resonant mass at 4 K is of the order of a few hundredths of a micro Kelvin. We show it is possible to measure such a low noise temperature in a Sapphire Dielectric Bar Transducer (SDBT). [1] R.A. Woode, M.E. Tobar, E.N. Ivanov, D.G. Blair, An ultra-low noise microwave oscillator based on a high-Q liquid nitrogen cooled sapphire resonator, to be published in IEEE Trans. on UFFC, 1996. And now for something comepletly different... I have found no John H. Sutton by searching the net this spring- http://www.nitehawk.com/Mystical.Crystal/atlcrpw.htm John H. Sutton, a NASA researcher involved with applications of low energy plasmas, believes that the Great Crystal Cayce was describing was a 'laser-fusion reactor/gravity wave generator.' He suggests that when intense gravity waves were generated by the Crystal and beamed into the Earth, the planet's crystalline quartz, which occurs in granite rock as high as 25 percent throughout the crust, absorbed the energy and the resulting melt-down of large masses of subterranean quartz would have been the triggering mechanism for causing major slippage along the Earth's fault-lines, destroying Atlantis and precipitating a global shift. ================ A good background info. link- http://www.piezo.com/histry.html ================ One loose end is a comment at a Japanese gravity science Website ( http://www.icrr.u-tokyo.ac.jp/gr/English/theory/resonant.html ) that piezo transducers on historic metal rod instruments did not work well at cryogenic temperatures. I do not yet know if this applies only to manmade ceramic piezo materials, or the magnitude of sensitivity loss, if any, by supercooled quartz or tourmaline.
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