Emergence of non-Fermi liquid dynamics through nonlocal correlations in an interacting disordered system

摘要

We provide strong evidence for a quantum critical point (QCP) associated with the destruction of Kondo screening in the Anderson-Hubbard model for interacting electrons with quenched disorder. The evidence comprises three elements: (a) the identification of an energy scale, ω~*. that delineates infrared Landau damping from higher frequency non-Fermi liquid(nFL) dynamics; (b) the finding that this crossover scale ω~* appears to vanish with increasing disorder; and (c) the concomitant appearance of a finite intercept in a broad distribution of Kondo scales. Our findings indicate a Kondo destruction scenario, albeit distinct from the local QCP picture. The nFL behavior is shown to stem from an interplay of strong electron-electron interactions and the systematic inclusion of short-range dynamical fluctuations induced by the underlying random potential. The results have been obtained through a computational framework based on the typical medium dynamical cluster approximation.