Quantum tunneling of massive flux lines in a high-Tc superconductor

We have investigated the quantum tunneling of damped flux lines of finite mass at T = 0 by extending our previous study of tunneling around T0, the transition temperature. In the case of a cubic pinning potential, considered here, the action could be evaluated in a closed form for a flux line of finite length. The tunneling rate reaches a finite limit at T = 0, although it is temperature dependent and exhibits a 1/T variation near T0. (orig.)