Spatial fluctuations of the pairing potential in disordered superconductors
نویسنده
چکیده
We study the effect of site diagonal, non-magnetic, disorder on the a pairing amplitude in an extended Hubbard model with the intersite attraction. Analyzing fluctuations of a pairing potential we discuss the instability of mixed solutions, ’s + d’ and ’s + id’, in presence of disorder. The influence of disorder on extended s– and d–wave superconductors appear to be comparable but in certain regions of the phase diagram, even weak disorder can change the symmetry of the order parameter.
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تاریخ انتشار 2001