Electromigration in the dissipative state of high-temperature superconducting bridges

The current stimulated atomic diffusion in YBa2Cu3O7 superconducting bridges is investigated. A superconductor to insulator transition can be induced by direct current controlled electromigration process whereas partial recovery of the superconducting state can be achieved by inverting the polarity of the bias. Interestingly, the temperature dependence of the current density Jem(T), above which atomic migration takes place intersects the critical current density Jc(T) at certain temperature T*. Therefore, for T<T* the superconducting dissipative state cannot be accessed without leading to irreversible modifications of the material properties. This phenomenon may also become an important mechanism of local sample deterioration in high critical temperature superconducting films abruptly penetrated by thermomagnetic instabilities.