Non Fermi liquid behavior and continuously tunable resistivity exponents in the Anderson-Hubbard model at finite temperature

Abstract

We employ a recently developed computational many-body technique to study for the first time the half-filled Anderson-Hubbard model at finite temperature and arbitrary correlation ($U$) and disorder ($V$) strengths. Interestingly, the narrow zero temperature metallic range induced by disorder from the Mott insulator expands with increasing temperature in a manner resembling a quantum critical point. Our study of the resistivity temperature scaling $T^{\alpha}$ for this metal reveals non Fermi liquid characteristics. Moreover, a continuous dependence of $\alpha$ on $U$ and $V$ from linear to nearly quadratic was observed. We argue that these exotic results arise from a systematic change with $U$ and $V$ of the "effective" disorder, a combination of quenched disorder and intrinsic localized spins.