Low phase noise temperature-compensated cryogenic whispering gallery mode resonator operated at 63 K in a closed cycle cooler

Whispering gallery modes in a miniature temperature compensated composite dielectric resonator (at T/spl sim/63 K) can exhibit loaded Q/sub L/ values above 10/sup 7/ at /spl sim/10 GHz, close to the Cs atomic clock frequency. The high Q of the dielectric resonators can be used to produce low phase noise oscillators limited only by the performance of amplifiers and mixers. Effective mechanical vibration isolation is also demonstrated in a Gifford-McMahon cooler.