High Q-factor sapphire whispering gallery mode microwave resonator at single photon energies and millikelvin temperatures
Abstract
The microwave properties of a crystalline sapphire dielectric whispering gallery mode resonator have been measured at very low excitation strength (E/ℏω≈1) and low temperatures (T≈30 mK). The measurements were sensitive enough to observe saturation due to a highly detuned electron spin resonance, which limited the loss tangent of the material to about 2×10−8 measured at 13.868 and 13.259 GHz. Small power dependent frequency shifts were also measured which correspond to an added magnetic susceptibility of order 10−9. This work shows that quantum limited microwave resonators with Q-factors >108 are possible with the implementation of a sapphire whispering gallery mode system.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 30, 2011
- Source ID
- 10.1063/1.3595942
Entities
People
- Daniel L. Creedon
- John M. Martinis
- Michael E. Tobar
- Timothy L. Duty
- Warrick Farr
- Yarema Reshitnyk
Organizations
- Army Research Office
- University of California
- University of Queensland
- University of Western Australia