Thermal and magnetic properties of a low-temperature antiferromagnet Ce$_4$Pt$_{12}$Sn$_{25}$

ORAL

Abstract

We report specific heat ($C$) and magnetization ($M$) of single crystalline Ce$_4$Pt$_{12}$Sn$_{25}$ at temperature down to $\sim$\,50\,mK and in fields up to 3\,T. $C/T$ exhibits a sharp anomaly at 180\,mK, with a large $\Delta$$C$/$T$\,$\sim$\,30\,J/mol\,K$^2$-Ce, which, together with corresponding the cusp-like magnetization anomaly, indicate antiferromagnetic (AFM) ground state with N\'eel temperature $T_{\mathrm{N}}$\,=\,0.18\,K. Numerical calculations based on Heisenberg model reproduce both specific heat and magnetization data, and point to a very small Kondo scale $T_K$, clearly placing Ce$_4$Pt$_{12}$Sn$_{25}$ in the weak exchange coupling $J < J_c$ limit of the Doniac diagram. Magnetic field suppresses AFM state at $H^* \approx 0.7$ T. Anomalous behavior observed in $M$($H$) vs. $T$ for fields in the vicinity of $H^*$ points to a likely field-induced quantum critical point (QCP) at $H^*$.

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Authors

  • R. Movshovich

    Los Alamos National Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • N. Kurita

    Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • H.-O. Lee

    Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • Y. Tokiwa

    Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • C.F. Miclea

    Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • Eric D. Bauer

    Los Alamos National Laboratory, New Mexico, USA, Los Alamos National Laboratory, LANL, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA, Los Alamos National Lab

  • F. Ronning

    Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • J.D. Thompson

    Los Alamos National Laboratory, LANL, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • P. Ho

    Department of Physics, California State University, Fresno, Fresno, California 93740

  • M. B. Maple

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

  • P. Sengupta

    National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA

  • I. Vekhter

    Louisiana State University, Department of Physics \& Astronomy, Louisiana State University, Baton Rouge, LA 70803, Department of Physics and Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, USA

  • Z. Fisk

    University of California - Irvine, University of California Irvine, UC Irvine, University of California, Irvine, California 92697, USA