Title :
A technique for high-power microwave diagnostics of large-area homogeneous HTS films
Author :
Reznik, A.N. ; Vorobiev, A.K. ; Pavlov, S.A. ; Parafin, A.E. ; Isaev, V.A. ; Gaikovich, K.P.
Author_Institution :
Inst. for Phys. of Microstruct., Acad. of Sci., Nizhny Novgorod, Russia
fDate :
6/1/1999 12:00:00 AM
Abstract :
A new technique and measuring equipment for determination of the dependence of HTS surface resistance on a microwave magnetic field amplitude, R/sub s/(H), were developed. The measuring system was an open 36 GHz resonator formed between a spherical metal surface and a flat HTS film. The microwave scheme included a high-power pumping wave circuit and a spectrally separated low-power diagnostic signal circuit. The H structure inhomogeneity on the HTS surface was taken into account. Measurements of the averaged surface resistance have shown it to be related with R/sub s/(H) by the integral equation. The technique for solution of the integral equation based on the Tikhonov method extended from the theory of incorrect inverse problems was applied. Some results of R/sub s/(H) measurements for large-area (>35 mm) YBCO films deposited onto NdGaO/sub 3/, LaAlO/sub 3/ substrates are presented and discussed.
Keywords :
barium compounds; ceramics; high-temperature superconductors; integral equations; inverse problems; microwave measurement; nondestructive testing; superconducting thin films; yttrium compounds; 36 GHz; LaAlO/sub 3/; LaAlO/sub 3/ substrate; NdGaO/sub 3/; NdGaO/sub 3/ substrate; YBaCuO; high-power microwave diagnostics; integral equation; large-area homogeneous HTS films; microwave magnetic field amplitude; new technique; spherical metal surface/flat HTS film resonator; Electrical resistance measurement; High temperature superconductors; Integral equations; Magnetic field measurement; Microwave circuits; Microwave devices; Microwave magnetics; Microwave measurements; Microwave theory and techniques; Surface resistance;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
