A one milliKelvin top-loading dilution refrigerator and demagnetization cryostat, and, The electric field dependence of the dielectric constant in amorphous materials at ultra-low temperatures.

摘要

A novel top-loading cryostat has been constructed which allows experimental samples to be cooled from room temperature to under 100 mK in 6 hours without warming the cryostat's sample plate above 200 mK. The cryostat uses dilution refrigeration and adiabatic demagnetization to reach an ultimate base temperature of 1 mK, achievable after precooling the demagnetization stage for 42 hours. Unusual cryostat design features include a hydraulic thermal clamp mechanism, a multi-segment top-load rod, and beryllium-copper fingers used for contact precooling of the sample carrier.;Non-linear behavior is observed in the AC dielectric response of amorphous SiO;References. Anthony, P. J. and A.C. Anderson, Phys Rev B, 0, 763 (1979). Frosati, G., Maynard, R. Rammal, and D. Thoulouze, Ler Journal de Physique--Lettres, 8, L-153 (1977).