DISORDER-INDUCED FLUCTUATIONS IN THE MAGNETIC-PROPERTIES OF AN ANDERSON-NUBBARD MODEL

We present a microscopic description of the inhomogeneous magnetic response of a disordered, interacting system, with local susceptibilities determined via a random-phase-approximation-type approach about stable, inhomogeneous mean-field ground states. A careful treatment of the role of disorder is vital in describing: the phase boundary to local moment formation; site-differential inhomogeneity in the distribution of local susceptibilities in a local moment regime, and its marked disorder-induced enhancement; and, on the length scales probed, large disorder-induced fluctuations in the total magnetic susceptibility. © 1995 The American Physical Society