A Comparative Study for the Microwave Surface Resistances of $YBa_2$$Cu_3$$O-{7-$\delta$}$ Films Measured with a Microstrip Resonator and a Inutile-loaded Cavity Resonator

마이크로스트립 공진기와 Rutile-loaded Cavity 공진기로 측정한 $YBa_2$$Cu_3$$O-{7-$\delta$}$박막의 마이크로파 표면저항 비교 연구

Temperature dependences of the unloaded Ｑ(Ｑ$_{0}$) and the resonant frequency ( $f_{0}$) of YB $a_2$C $u_3$ $O_{7-{\delta}}$ (YBCO) microstrip ring resonators and rutile-loaded cylindrical cavity resonators were measured at low temperatures. Dc magnetron-sputtered YBCO films grown on Ce $O_2$-buffered r-cut sapphire (CbS) substrates were used fur this purpose. The surface resistances ( $R_{s}$) of YBCO films measured by both a microstrip ring resonator and a TE $01\delta$/ mode rutile-loaded cylindrical cavity resonator are compared with each other. It turned out that the values of $R_{s}$ measured by the microstrip resonator technique are comparable to those by the rutile-loaded resonator technique at temperatures lower than ~50 K. However, above 50 K, the $R_{s}$ measured by the microstrip resonator technique appeared higher according to the temperature. Our results show that the current crowding effects near the edge of a microstrip resonator become more significant at temperatures near the critical temperature.emperature.e.e.e.e.e.e.