On dissipation and noise in weak superfluidity : the example of YBaCuO

Abstract

In the high-Tc superconductors, thermal activation of vortex motion or phase slippage reduces the critical current Jc to practically zero between Tc and a nearby "irreversibility" point Tirr. The latter behaves as a marginal-stability point and intrinsic intense 1/f noise is expected there, consistently with recent experimental findings