STABILITY OF THE NORMAL-PHASE IN A BOUNDED CURRENT-CARRYING SUPERCONDUCTING FILM

The two-phase equilibrium states of a current-carrying thin supercondu cting film in the case of convective heat transfer on the free surface are considered, and their stability is investigated in a first approx imation. It is shown that of the two equilibrium states, the state wit h the normal-phase region of larger size is stable. In the limiting ca se of an infinitely long film, the stable two-phase equilibrium state tends to a spatially uniform normal state, and the unstable state rema ins localized. In a definite range of values of the system parameters, the relaxation time of such a formation can be fairly long, and it sh ould be regarded as a quasistable equilibrium state. (C) 1998 American Institute of Physics. [S1063-7842(98)01406-8].