Title :
Microwave absorption of YBa/sub 2/Cu/sub 3/O/sub 7/ thin films with columnar defects
Author :
Lofland, S.E. ; Huang, M.X. ; Bhagat, S.M. ; Rajeswari, M. ; Venkatesan, Thirumalai ; Kanjilal, D. ; Senapati, L. ; Mehta, G.K.
Author_Institution :
Dept. of Phys., Maryland Univ., College Park, MD, USA
fDate :
6/1/1995 12:00:00 AM
Abstract :
We have measured the microwave magnetoabsorption of both pristine and irradiated c-axis-oriented YBa/sub 2/Cu/sub 3/O/sub 7/ thin films. The irradiation was done using 270-MeV Ag ions and produces columnar defects along the film normal. The angular dependence of the absorption for pristine films can be described by sin/spl theta/; where /spl theta/ is the inclination of the field from the film plane. However, there is a minimum in the magnetoabsorption of the irradiated films when the applied field is parallel to the columns. This minimum is indicative of vortex localization as predicted by Nelson and Vinokur. We believe that this is the first high-frequency measurement of this phenomenon.<>
Keywords :
barium compounds; electromagnetic wave absorption; high-temperature superconductors; ion beam effects; magnetoabsorption; superconducting thin films; yttrium compounds; 270 MeV; Ag; Ag ion irradiation; YBa/sub 2/Cu/sub 3/O/sub 7/; YBa/sub 2/Cu/sub 3/O/sub 7/ thin films; columnar defects; high-frequency measurement; magnetoabsorption; microwave absorption; vortex localization; Electromagnetic wave absorption; Magnetic field measurement; Nuclear and plasma sciences; Pulse measurements; Superconducting magnets; Superconducting microwave devices; Superconducting thin films; Superconductivity; Transistors; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
