Quasiparticle Relaxation in Optically Excited High-Q Superconducting Resonators
Abstract
The quasiparticle relaxation time in superconducting films has been measured as a function of temperature using the response of the complex conductivity to photon flux. For tantalum and aluminum, chosen for their difference in electron-phonon coupling strength, we find that at high temperatures the relaxation time increases with decreasing temperature, as expected for electron-phonon interaction. At low temperatures we find in both superconducting materials a saturation of the relaxation time, suggesting the presence of a second relaxation channel not due to electron-phonon interaction.
- Publication:
-
Physical Review Letters
- Pub Date:
- June 2008
- DOI:
- 10.1103/PhysRevLett.100.257002
- arXiv:
- arXiv:0802.0640
- Bibcode:
- 2008PhRvL.100y7002B
- Keywords:
-
- 74.25.Nf;
- 74.40.+k;
- Response to electromagnetic fields;
- Fluctuations;
- Condensed Matter - Superconductivity;
- Condensed Matter - Mesoscopic Systems and Quantum Hall Effect
- E-Print:
- 4 pages, 3 figures