INTERPLAY BETWEEN THE ANDERSON MODEL OF LOCALIZATION AND BCS SUPERCONDUCTIVITY - THE FINITE BAND-WIDTH TRANSITION

We combine the tight binding Anderson model of disorder with a mean fi eld BCS interaction. The transition temperature is obtained as a gener al relation which depends on the disorder averaged spectral density as sociated with the electron propagator between neighboring lattice site s. This relation is obtained using the locator expansion technique. As a main result we predict superconductivity in the disorder induced lo calized state. There is a maximun bandwidth where superconductivity is destroyed. This is consequence of the local pairing assumed in the mo del..