Title :
The surface resistance of bulk polycrystalline YBa/sub 2/Cu/sub 3/O/sub 7/(-X)
Author :
Tonkin, B.A. ; Proykova, Y.G.
Author_Institution :
Div. of Phys., Portsmouth Polytech., UK
fDate :
6/1/1995 12:00:00 AM
Abstract :
The surface resistance of viscous processed and powder processed bulk polycrystalline YBa/sub 2/Cu/sub 3/O/sub 7-X/ specimens have been measured as a function of frequency (27-38 GHz) and temperature (10-150 K) using an endwall replacement technique. The surface resistance of the viscous processed material within the 9-38 GHz frequency region gives a crossover frequency of 7.6 GHz. The temperature dependence of the superconducting state of material from both processing methods can be described by a two-gap BCS model which treats the sample as a network of weakly coupled superconducting grains.<>
Keywords :
BCS theory; barium compounds; ceramics; high-frequency effects; high-temperature superconductors; materials preparation; powder technology; surface conductivity; yttrium compounds; 10 to 150 K; 9 to 38 GHz; YBa/sub 2/Cu/sub 3/O/sub 7/; bulk polycrystalline YBa/sub 2/Cu/sub 3/O/sub 7-X/; crossover frequency; endwall replacement technique; frequency dependence; powder processing; surface resistance; temperature dependence; two-gap BCS model; viscous processing; weakly coupled superconducting grains; Electrical resistance measurement; Frequency measurement; Impurities; Microwave measurements; Powders; Superconducting transition temperature; Surface resistance; Temperature dependence; X-ray diffraction; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
