Weak hybridization and isolated localized magnetic moments in the compounds CeT$_2$Cd$_{20}$ (T = Ni, Pd)

ORAL

Abstract

Large Ce-Ce distances of 6.7-6.8~\AA~and weak hybridization between Ce 4$f$ and itinerant electron states act to promote stable localized magnetic moments in the compounds CeT$_2$Cd$_{20}$ (T = Ni, Pd), but also conspire to severely limit the strength of the Ruderman-Kittel-Kasuya-Yosida (RKKY) magnetic exchange interaction that couples them. As a consequence, measurements of electrical resistivity, performed on single-crystalline samples of these new Cd-based compounds down to 0.138 K, were unable to resolve any evidence for magnetic order. In this presentation, we will compare measurements of the physical properties of CeT$_2$Cd$_{20}$ (T = Ni, Pd) under ambient and applied pressures with the reported properties of the isostructural compounds CeT$_2$X$_{20}$ (T = transition metal; X = Al, Zn). We will use these comparisons to discuss the interplay of unit cell volume, hybridization, and the RKKY interaction and its role in establishing the ground states of the Ce-based ``1-2-20'' compounds.

*Sample synthesis and physical properties measurements were supported by the U.S. DOE under grant no. DE-FG02-04-ER46105. Measurements of electrical resistivity below 1 K were supported by the NSF under grants no. DMR-1206553 and no. DMR-1104544.

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Authors

  • B. White

    • University of California, San Diego
    • Physics Department, UC San Diego
    • Department of Physics, University of California, San Diego
    • Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA

  • D. Yazici

    • Physics Department, UC San Diego
    • Department of Physics, University of California, San Diego
    • UC, San Diego
    • Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA

  • P.-C. Ho

    • Department of Physics, California State University, Fresno
    • Physics/CSU-Fresno

  • Noravee Kanchanavatee

    • Department of Physics, University of California, San Diego

  • Naveen Pouse

    • Physics Department, UC San Diego
    • Department of Physics, University of California, San Diego

  • Aaron Friedman

    • Department of Physics, University of California, San Diego

  • Brian Maple

    • University of California, San Diego
    • Physics Department, UC San Diego
    • Department of Physics, University of California, San Diego
    • Physics/UC San Diego
    • Department of Physics, University of California, San Diego, La Jolla, CA 92093, USA
    • Department. of Physics, U. of California, San Diego