Title :
Surface impedance measurements on high-T/sub c/ superconductors using a far-infrared laser
Author :
Kawate, E. ; Mossavati, R. ; Okaji, M. ; Ito, T. ; Ohashi, Y. ; Moe, A.M. ; Oka, K.
Author_Institution :
Nat. Res. Lab. of Metrol., Ibaraki, Japan
fDate :
6/1/1997 12:00:00 AM
Abstract :
A novel method of absorption measurements is reported through which we have succeeded in measuring directly the absolute absorptivity of a La-based superconductor in the 100 GHz to 500 THz frequency region using different lasers. We have made transmission measurements on free standing single crystals of the La-based superconductor using a laser and a high sensitivity detector, and succeeded in measuring the transmissivity. For the first time, the surface impedance has been analytically derived from the absorptivity and transmissivity at room temperature.
Keywords :
electric impedance measurement; high-temperature superconductors; lanthanum compounds; light absorption; light transmission; measurement by laser beam; millimetre wave measurement; optical conductivity; skin effect; strontium compounds; submillimetre wave measurement; 100 GHz to 500 THz; FIR region; La-based superconductor; La/sub 1.85/Sr/sub 0.15/CuO/sub 4/; LaSrCuO; absolute absorptivity; absorption measurements; far-infrared laser; free standing single crystals; high sensitivity detector; high-T/sub c/ superconductors; room temperature; surface impedance measurements; transmission measurements; transmissivity; twice absorptive laser calorimetric method; Crystals; Frequency measurement; High temperature superconductors; Impedance measurement; Laser cavity resonators; Optical surface waves; Superconducting microwave devices; Superconducting photodetectors; Surface emitting lasers; Surface impedance;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
