Hall tunneling of vortices in superclean superconductors

We discuss the main features of Hall tunneling of pancake vortices in superclean high-$T_c$ superconductors. The general formalism for the calculation of the lifetime of a vortex pinned in a metastable configuration is described. The results are applied to the problem of quantum tunneling of a pancake vortex from a columnar defect in the limit of a small driving current.