Title :
Melt-textured YBa/sub 2/Cu/sub 3/O/sub 7/ for low-field applications in microwave devices
Author :
Bai, V.S. ; Bhagat, S.M. ; Rajasekharan, T.
Author_Institution :
Center for Supercond. Res., Maryland Univ., College Park, MD, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
We report the results of an investigation of microwave power loss at 10 GHz in YBCO at 77 K. The samples are melt-textured YBa/sub 2/Cu/sub 3/O/sub 7/ (123) with 28 mole % Y/sub 2/BaCuO/sub 5/ (211) inclusions and x% of Ag added to bridge the gaps at the grain boundaries. The sample with 10% Ag shows critical currents >10/sup 8/ amp/m/sup 2/ at 77 K. Measurements down to 77 K show that microwave power loss drops more sharply (through T/sub c/ of 89 K) with higher Ag content. DC magnetic-field-induced microwave absorption (MWMA) recorded at 77 K shows that in these samples the low (/spl sim/10 mT) field loss is drastically reduced with respect to that in typical YBCO ceramics.<>
Keywords :
barium compounds; ceramics; critical currents; electromagnetic wave absorption; grain boundaries; high-temperature superconductors; inclusions; losses; magnetoabsorption; superconducting microwave devices; superconducting transition temperature; texture; yttrium compounds; 10 GHz; 77 K; 89 K; DC magnetic-field-induced microwave absorption; Y/sub 2/BaCuO/sub 5/; Y/sub 2/BaCuO/sub 5/ inclusions; YBa/sub 2/Cu/sub 3/O/sub 7/; YBa/sub 2/Cu/sub 3/O/sub 7/-Ag; ceramic superconductors; critical currents; grain boundaries; high temperature superconductors; low-field applications; melt-textured YBa/sub 2/Cu/sub 3/O/sub 7/; microwave devices; microwave magnetoabsorption; microwave power loss; superconducting transition temperature; Bridges; Critical current; Current measurement; Electromagnetic wave absorption; Grain boundaries; Loss measurement; Magnetic field measurement; Microwave measurements; Power measurement; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
