PACS. 72.15.Rn -Localization effects (Anderson or weak localization). PACS. 71.27.+a -Strongly correlated electron systems; heavy fermions. PACS. 71.30.+h -Metal-insulator transitions and other electronic transitions.Abstract. -We present a self-consistent theory of Anderson localization that yields a simple algorithm to obtain typical local density of states as an order parameter, thereby reproducing the essential features of a phase-diagram of localization-delocalization quantum phase transition in the standard lattice models of disordered electron problem. Due to the local character of our theory, it can easily be combined with dynamical mean-field approaches to strongly correlated electrons, thus opening an attractive avenue for a genuine non-perturbative treatment of the interplay of strong interactions and strong disorder.c EDP Sciences

A model of spinless interacting electrons in presence of randomness is examined using an extended dynamical mean-field formulation. When the interaction strength is large as compared to the Fermi energy, a low temperature glassy phase is identified, which in our formulation corresponds to a replica-symmetry breaking instability. The glassy phase is characterized by a pseudo-gap in the single particle density of states, reminiscent of the Coulomb gap of Efros and Shklovskii. Due to ergodicity breaking, the ``zero-field cooled'' compressibility of this electron glass vanishes at T=0, consistent with absence of screening. When the Fermi energy exceeds a critical value, the glassy phase is suppressed, and normal metallic behavior is recovered.Comment: 4 pages, 2 figures; minor corrections and new footnotes adde

The emergence of glassy behavior of electrons is investigated for systems close to disorder-driven and interaction-driven metal-insulator transitions. Our results indicate that Anderson localization effects strongly stabilize such glassy behavior, while Mott localization tends to suppress it. We predict the emergence of an intermediate metallic glassy phase separating the insulator from the normal metal. This effect is expected to be most pronounced for sufficiently disordered systems, in agreement with recent experimental observations.