Thermal depinning of flux lines in HgBa{sub {bold 2}} CuO{sub {bold 4+{delta}}} from {sup 199}Hg spin-lattice relaxation
- Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States)
{sup 199}Hg NMR spin-lattice relaxation rates in an aligned powder sample of the anisotropic high-{ital T}{sub {ital c}} superconductor HgBa{sub 2}CuO{sub 4+{delta}} ({ital T}{sub {ital c}}=96 K) show anisotropy in the temperature interval 10{endash}50 K, with an extra contribution present for the external magnetic field parallel to the {ital c} axis. The extra contribution shifts with magnetic field in a way related to the irreversibility temperature {ital T}{sub irr}, indicating that the thermal motion of flux lines (FL{close_quote}s) is the cause of the extra relaxation. A simple model is presented to analyze the relaxation data and to extract values for the correlation time {tau}{sub {ital c}} and the effective activation energy {ital U} of the FL motion. {copyright} {ital 1996 The American Physical Society.}
- Research Organization:
- Ames National Laboratory
- DOE Contract Number:
- W-7405-ENG-82
- OSTI ID:
- 284426
- Journal Information:
- Physical Review Letters, Vol. 76, Issue 11; Other Information: PBD: Mar 1996
- Country of Publication:
- United States
- Language:
- English
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