Theoretical calculations for disordered d-wave superconductors

We calculate the distributions P[Delta(0)(r(i))] of local d-wave pairing amplitudes Delta(0)(r(i)) and P[rho(0)(r(i))] of local density of charge carriers rho(r(i)) for the La2-xSrxCuO4 high-temperature superconductor (HTSC) family in a disordered two-dimensional medium. To reproduce the observed inhomogeneity a random potential V-imp, within a Bogoliubov-de Gennes (BdG) formalism, is considered. The calculations show that the underdoped compounds are more inhomogeneous than the overdoped ones. Also, the spatial variation of Delta(0)(r(i)) decreases as the average density of charge carriers <rho > increases, demonstrating that the system becomes more homogeneous for high values of <rho >. (c) 2007 Elsevier B.V. All rights reserved.