$^{7}$Li NMR Study of Yb$_{4}$LiGe$_{4}$: A Possible Kondo Insulator

ORAL

Abstract

We report on the temperature-dependent resistivity, magnetic susceptibility, and nuclear spin-lattice relaxation rate of polycrystalline Yb$_{4}$LiGe$_{4}$. The parent compound, Yb$_{5}$Ge$_{4}$, is known to be mixed valent. The increasing susceptibility and resistivity with decreasing temperature are consistent with a Kondo insulator. Measurements of the temperature dependent $^{7}$Li spin-lattice relaxation rate $1/T_{1}$ show an increasing rate for decreasing temperature ($T \quad >$ 50 K), followed by a broad maximum near 30 K. These results are discussed in light of the heavy-fermion like nature of the material.

*Work supported by NSF Materials World Network grant DMR-0710525

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Authors

  • M. J. Graf

    • Physics Department. Boston College.
    • Department of Physics, Boston College, Chestnut Hill, MA 02467 USA
    • Physics Department. Boston College
    • Dept. of Physics, Boston College, Chestnut Hill, MA 02467, USA

  • V. Lanio

    • Dept. of Physics, Boston College, Chestnut Hill, MA 02467, USA

  • P. Carretta

    • Dept. of Physics A. Volta, Univ. of Pavia, 27100 Pavia, Italy

  • Yu. Grin

    • Max-Planck-Institut fur Chemische Physik fester Stoffe, 01187 Dresden, Germany

  • S. Peter

    • Max-Planck-Institut fur Chemische Physik fester Stoffe, 01187 Dresden, Germany