Title :
Flux-line pinning in polycrystalline La1.85Sr0.15 CuO4 irradiated with swift heavy ions
Author :
Mitamura, Takeshi ; Terasawa, M. ; Fan, X. ; Kohara, T. ; Ueda, K. ; Tsubakino, H. ; Yamamoto, A. ; Kambara, T. ; Matsubara, I. ; Murakami, Toshiyuki
Author_Institution :
Himeji Inst. of Technol., Himeji, Japan
Abstract :
The vortex pinning phenomena were investigated in type II high temperature superconducting material, polycrystalline La1.85Sr0.15CuO4 to which 3.5 GeV Xe ion end 26 GeV Ar ion were irradiated. Changes of superconducting characteristics were measured before and after the ion irradiations using a superconducting quantum interference device (SQUID). In Xe irradiation as well as Ar irradiation, reduction of normalized rate of magnetic relaxation was observed. The reduction rate of Xe ion irradiated specimen was much larger than that of the Ar ion irradiated one. However, in polycrystalline LSCO, existence of grains with various directions and numerous grain boundaries may take considerable roles to pin vortex together with columnar defects. It appears that the creep rate obtained substantiates the collective creep model of the vortex
Keywords :
argon; flux creep; flux pinning; flux-line lattice; grain boundaries; high-temperature superconductors; ion beam effects; lanthanum compounds; magnetic relaxation; strontium compounds; xenon; 26 GeV; 3.5 GeV; La1.85Sr0.15CuO4:Ar; La1.85Sr0.15CuO4:Xe; collective creep model; columnar defects; flux-line pinning; grain boundaries; high temperature superconductors; magnetic relaxation; polycrystalline material; swift heavy ion irradiation; vortex pinning; Argon; Creep; High temperature superconductors; Interference; SQUIDs; Strontium; Superconducting devices; Superconducting magnets; Superconducting materials; Type II superconductors;
Conference_Titel :
Ion Implantation Technology Proceedings, 1998 International Conference on
Conference_Location :
Kyoto
Print_ISBN :
0-7803-4538-X
DOI :
10.1109/IIT.1998.813873
