Im. Fishman et al., MODULATION MEASUREMENTS OF YBA2CU3O7-X OPTICAL REFLECTIVITY USING A THERMAL-WAVE TECHNIQUE, Physica. C, Superconductivity, 249(3-4), 1995, pp. 304-308
We have measured the differential optical reflectivity (lambda = 0.78
mm) of YBa2Cu3O7-x single crystals in the temperature range of 20-300
K using a thermal wave technique. A sharp signal maximum with a temper
ature width similar to 10 K was observed below T-c, and was attributed
to the electronic contribution of the optical reflectivity. It is con
cluded that the two components of the differential reflectivity signal
are related to accumulation of, the superconducting phase and tempera
ture variation of the electron-scattering time.