Abstract
199Hg NMR spin-lattice relaxation rates in an aligned powder sample of the anisotropic high- Tc superconductor HgBa2CuO4+δ (Tc = 96 K) show anisotropy in the temperature interval 10-50 K, with an extra contribution present for the external magnetic field parallel to the c axis. The extra contribution shifts with magnetic field in a way related to the irreversibility temperature Tirr, indicating that the thermal motion of flux lines (FL’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 τc and the effective activation energy U of the FL motion.
Original language | English |
---|---|
Pages (from-to) | 1928-1931 |
Number of pages | 4 |
Journal | Physical Review Letters |
Volume | 76 |
Issue number | 11 |
DOIs | |
State | Published - 11 Mar 1996 |