RELAXATION OF CHARGE IMBALANCE IN A D-WAVE SUPERCONDUCTOR

We study the effect of a nonmagnetic impurity on the relaxation of the charge imbalance in ad-wave superconductor. We compute the electric f ield as a function of distance in the normal-metal-superconductor junc tion. while taking into account the effect of the impurity scattering, gap anisotropy, Andreev scattering, and crystal orientation of the or der parameter. We compare the results with a highly anisotropic s-wave superconductor and also discuss the effect of the electron-phonon sca ttering.