Vibratory motion of vortices near the surface of type II superconductor under the AC magnetic field
The vibrational contribution $\mu_{v}(H)$ to the dynamic magnetic permeability is calculated allowing for the spatial variation of the order parameter in the vortex cores. The behavior of calculated dependence $\mu _{v}(H)$ is analyzed for the case when the vortices oscillate near their positions corresponding to the equilibrium vortex lattice. It is shown that taking into account the suppression of the order parameter in the vortex cores leads to appreciable difference in the behavior of $\mu_{v}(H)$ as compared to the similar dependence obtained in the London approximation. The main reason of this difference is a change of the effective potential well in which the vibrational motion of the vortices takes place.