The use of aluminum alloy 5056 for high-Q mechanical oscillators at low temperatures

P. W. Adams, Louisiana State University
Jing Chun Xu, Louisiana State University


Measurements of the quality factor (Q) and period (P0) of two Al 5056 torsional oscillators are presented as a function of temperature from 0.02 to 1.2 K. The 5056 alloy is found to have Q's of order 104 at room temperature and 107 below 4 K. In addition to having an extraordinary high Q, we also find that the temperature dependence of the reduced period, ΔP/P0, is extremely weak at low temperatures, making this material well suited for superfluid helium film studies. A technique for attaching thin dielectric substrates to the torsion member of one of the oscillators is also discussed.