Title :
Microwave properties of bulk and thick film YBCO
Author :
Tonkin, B.A. ; Proykova, Y.G.
Author_Institution :
Dept. of Appl. Phys. & Phys. Electron., Portsmouth Univ., UK
fDate :
3/1/1993 12:00:00 AM
Abstract :
The surface impedance of bulk polycrystalline and melt-processed thick film YBCO specimens has been measured using a TE/sub 0mn/ resonant cavity endwall-replacement technique over the frequency range 9-18 GHz and the temperature range 10-200 K. A comparison between the two forms of the material confirms the superiority of the thick film at 77 K, but, because of large residual losses associated with the thick film, the bulk polycrystalline material is better below 50 K. Intrinsic behavior has been observed within a limited temperature range and comparison made with the Pippard and BCS expressions.<>
Keywords :
BCS theory; barium compounds; high-frequency effects; high-temperature superconductors; penetration depth (superconductivity); surface conductivity; yttrium compounds; 10 to 200 K; 9 to 18 GHz; BCS expressions; Pippard expression; TE/sub 0mn/ resonant cavity endwall-replacement technique; YBa/sub 2/Cu/sub 3/O/sub 7-x/; bulk polycrystalline material; melt-processed thick film; microwave properties; penetration depth; surface impedance; surface resistance; thick film YBCO; Frequency measurement; Impedance measurement; Loss measurement; Resonance; Surface impedance; Tellurium; Temperature distribution; Thick films; Thickness measurement; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
