Tuesday, 08/19/08

Session Title:	Flux Pinning and Dynamics II - Engineered Pinning Arrangements
Session Chairs:	Paul Barnes, Air Force Research Laboratory, Wright-Patterson AFB & Takanobu Kiss, Kyushu University
Paper Number:	2MPD04
Start Time:	10:00am
Session Type:	Poster

Matching field effects in Y123 films with 2-D APCs M. Takamura, M. Mukaida, R. Teranishi, K. Yamada, N. Mori, Japan / Kyushu Univ.; S. Horii, J. Shimoyama, Japan / Univ. of Tokyo; A. Ichinose, Japan / CRIEPI; R. Kita, Japan / Shizuoka Univ.; M. Namba, S. Awaji, K. Watanabe, Japan / Tohoku Univ.; K. Matsumoto, Japan / Kyushu Inst. of Tech.; Y. Yoshida, Japan / Nagoya Univ.

We investigated field angular dependences of JC and irreversibility lines for Y123 films with 2-dimensional artificial pinning centers (2-D APCs) by growing a-axis oriented Y123/Pr123 multilayer films. In the multilayer film, the a-axis oriented Y123 and the a-axis oriented Pr123 were stacked alternately on SrLaGaO4 substrates. We revealed that the Y123/Pr123 multilayer films have c-axis correlated pinning centers by measuring magnetic field angular dependences of JC. The magnetic field dependences of the JC (B//c) / JC (B//a) showed a maximum around the calculated matching field of the Y123/Pr123 multilayer films. The JC (B//c) / JC (B//a) may indicate trapping rate of vortices in RE123 films with c-axis correlated pinning centers. For a pure Y123 film and the two multilayer films which have the different APC spacing, the irreversibility lines normalized by TC at B//c were close to each other. On the other hand, the irreversibility lines at B//a were shifted to upper temperatures and magnetic fields with increasing APC spacing in the Y123/Pr123 multilayer films.