With a bolometric technique, we have measured, in intense fields, the low temperature microwave surface resistance of 90-K and 60-K YBCO single crystals. From the viscosity inferred from the field dependence of surface resistance, the quasiparticle scattering rate 1/τ in the vortex core of YBCO is found to be strongly suppressed. The long relaxation times of quasiparticle place YBCO in the "superclean regime" where the lifetime broadening of the core energy levels is much less than the energy spacing.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering