Abstract
With the vibrating-reed technique we have studied the coupling of the flux-line-lattice (FLL) to the atomic lattice between 4.2 and 100 K at constant applied fields 0.014T≤≤4 T in three different Bi-based polycrystalline samples. Depinning of the FLL is observed at temperatures above where a peak occurs in the damping of the vibrating sample. With increasing temperature, the FLL dissipation changes at from a hysteretic to a viscous regime. The depinning temperature <() follows a logarithmic magnetic field dependence which is similar to the dependence of the depinning temperature obtained from measurements of the electrical resistivity due to thermally activated flux motion.
- Received 12 April 1989
DOI:https://doi.org/10.1103/PhysRevLett.63.1869
©1989 American Physical Society