Studies on the rf squid effect in tl-ca-ba-cu-o thin films prepared by the spray pyrolysis technique

Abstract

RF SQUID behaviour in thin films of Tl-Ca-Ba-Cu-O has been studied. The films were prepared by the spray pyrolysis technique. Two films (A and B) which have Tc(R=0) values of 85 K and 103 K respectively, were chosen for the RF SQUID studies. Film A consists mainly of 2122 phase with needle-like grains whereas film B mainly consists of 2223 phase with well connected plate-like grains. RF SQUID modulations in film B were observed up to 101 K. The SQUID was also operated in flux-looked-loop mode. The RF SQUID fabricated from film B was found to exhibit better flux noise performance than that fabricated from film A. © 1994 IOP Publishing Ltd.