The Effects of Grinding on the Magnetic Susceptibility of UCu$_{3.95}$Ni$_{1.05}$

ORAL

Abstract

The effects of grinding on the magnetic susceptibility of UCu$_{3.95}$Ni$_{1.05}$ were studied in order to understand magnetization measurements in this material. Substantial information was recovered from these experiments, which were done at temperatures ranging from 3K to 300K and magnetic fields from 500 Oe to 4.75 kOe. For instance, a new and unexpected ferromagnetic (FM) phase transition was found at about 150~K in both ingot and powder samples. Similarly the magnetic properties of the powder seem to differ slightly from the ingot's. The powder's magnetic susceptibility $\chi_{\rm pwd}$ appears greater than the ingot's $\chi_{\rm ing}$ at all temperatures measured, with the difference $\Delta\chi=\chi_{\rm pwd}-\chi_{\rm ing}$ increasing with decreasing temperature. We analyze the observed $\Delta\chi$ in terms of two potential sources: impurities added to the powder during the grinding process and the effects of sample geometries in combination with the presence of a second (FM) phase in the studied material. We discuss how the measured differences might affect the study of the physics of this non-Fermi liquid/quantum critical compound.

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Authors

  • Carlos Sanchez

    Physics and Astronomy Department, California State University, Los Angeles, CA

  • Carmen Quen

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

  • Edith Soto

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

  • 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