Physics of the Solid State, Vol. 45, No. 3, 2003, pp. 409–413. Translated from Fizika Tverdogo Tela, Vol. 45, No. 3, 2003, pp. 385–389. Original Russian Text Copyright © 2003 by Artemov, Medvedev. METALS AND SUPERCONDUCTORS Phase Diagram of a Wide Current-Carrying Superconducting Film A. N. Artemov and Yu. V. Medvedev Donetsk Physicotechnical Institute, National Academy of Sciences of Ukraine, Donetsk, 83114 Ukraine e-mail:
[email protected] Received December 14, 2001; in final form, May 18, 2002 Abstract—A model of current heating of a wide superconducting film is suggested assuming nonlinearity of the film conductance. Within this model, the parameters of the film can be characterized by a single dimension- less coefficient of thermal balance which includes both thermal and resistive parameters of the system. The sta- bility of the state of the current-carrying film is analyzed. A phase diagram of the film is constructed in terms of the coefficient of thermal balance and the average current density. The propagation velocity of a stationary nonuniform temperature distribution in the film is calculated as a function of current density at various values of the coefficient of thermal balance. © 2003 MAIK “Nauka/Interperiodica”. 1. INTRODUCTION resistive region in order to characterize the power of A current-carrying type-II superconductor is a heat source Q˙ (J, T) in the conductor. For composite rather complex object. Depending on temperature and superconductors and narrow superconductive films, current density, it can exhibit a superconducting, resis- this analysis is commonly simplified by using a one- tive, or normal state.