Time-resolved quasiparticle dynamics of the itinerant antiferromagnet UPtGa$_{5}$

ORAL

Abstract

Time-resolved photoinduced reflectivity is measured in the spin-density-wave phase of the itinerant antiferromagnet UPtGa$_{5}$. Two relaxation components were seen: (a) a slow component whose amplitude appears below $T_{N}$, and relaxation time $\tau_{slow}$ exhibits an upturn near $T_{N}$; (b) the fast component persists at all temperatures, with the relaxation time $\tau_{fast}$ also exhibiting an upturn near $T_{N}$. Comparing with pump-probe data on UNiGa$_{5}$, the differences are explained in the context of UPtGa$_{5}$ having A-type, (rather than G-type) antiferromagnetism, resulting in partial Fermi surface nesting, partial gapping and consequently finite density of states, at the Fermi surface.

*MOE AcRF Tier 1 (RG41/07), Tier 2 (ARC 23/08), and NRF-CRP4-2008-04

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Authors

  • Elbert Chia

    • Nanyang Technological University

  • Jian-Xin Zhu

    • Theoretical Division, Los Alamos National Laboratory
    • Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
    • Los Alamos National Laboratory
    • Theoretical Division, Los Alamos National Laboratory, Los Alamos, NM 87545

  • Diyar Talbayev

    • Tulane University

  • H.J. Lee

    • University of California at Berkeley

  • Namjung Hur

    • Inha University

  • N.O. Moreno

    • Federal University of Sergipe

  • R.D. Averitt

    • Boston University

  • J.L. Sarrao

    • Los Alamos National Laboratory

  • Antoinette Taylor

    • CINT, Los Alamos National Laboratory
    • Los Alamos National Laboratory