Non-Fermi vs. Inhomogeneous-Fermi Liquid behaviour in UCu$_4$Ni in the context of the Kondo Disorder Model

ORAL

Abstract

UCu$_4$Ni is a site-disordered material with diverging thermodynamic and anomalous transport properties. Local nuclear magnetic resonance (NMR) experiments in combination with bulk magnetic susceptibility $\chi$ measurements performed on the same samples indicate that the low-temperature divergence of $\chi$ might be due in part to the presence of paramagnetic impurities. In this contribution, we describe the magnetization in terms of a Kondo disorder model and extract a set of parameters of the distribution of Kondo temperatures, which indicate that the low temperature side of the distribution does not have sufficient area to accommodate a non-Fermi liquid divergence. We use the same parameters to subsequently calculate the specific heat $C$ and to extrapolate to low temperatures, which allows us to compare with the known divergence of the magnetic contribution to $C/T$ below 10~K. We discuss to what extent the physics of this material is that of a non-Fermi liquid as opposed to an inhomogeneous Fermi fluid.

*Work supported by NSF-DMR 1105380

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Authors

  • Ariana Valdez

    • Department of Physics and Astronomy, California State University, Los Angeles, CA 90032

  • Oscar Bernal

    • Deparment of Physics and Astronomy, California State University, Los Angeles, CA 90032
    • Department of Physics and Astronomy, California State University, Los Angeles, CA 90032
    • Physics and Astronomy Department, California State University, Los Angeles, CA

  • G.R. Stewart

    • Department of Physics, University of Florida
    • Physics Department, University of Florida, Gainesville, FL
    • Department of Physics, University of Florida, Gainsville FL 32611

  • J.S. Kim

    • Department of Physics, University of Florida, Gainsville FL 32611