Weak magnetoresistance of disordered heavy fermion systems

Abstract

We compare the magnetoresistance of UCu${}_{3.5}$Pd${}_{1.5}$ with calculations done within the disordered heavy fermion framework of Miranda et al. using a phenomenological spectral function for the Anderson model, calibrated against Bethe ansatz and quantum Monte Carlo results. Both in experiment and theory, we find a weak negative magnetoresistance. In contrast, thermodynamic quantities have a strong field dependence. Using qualitative arguments broad distribution of Kondo scales, we explain the different field dependence of susceptibility and resistivity.

4 pages, 3 figures