Study of stimulated dynamics and pinning of Abrikosov vortex lattice in type II superconductors in an ac magnetic field

A dynamic mechanical method using a weak low-frequency magnetic field is proposed for investigation of stimulated dynamics and pinning in the Abrikosov vortex lattice in type II superconductors. It is shown that the application of a weak a. c. field facilitates depinning of Abrikosov vortices and additional dissipation of energy by liberated vortices. As the frequency of the field increases, a mode in which the vortices virtually do not oscillate is attained, i. e., dissipation ceases, while pinning is extremely effective. The observed effects can be successfully explained on the basis of the Gor'kov-Kopnin theory. (C) 1998 American Institute of Physics. [S1063-777X(98)00310-7]