Field Angle Tuned Metamagnetism, Lifschitz Transitions and Hidden Order in UPt<sub>3</sub>

ORAL

Abstract

We report ultrasound velocity measurements carried out on single crystals of UPt3, in magnetic fields, B, applied at various angles between c-axis and the basal plane. For B||c-axis, θ=90o, we observe magneto-acoustic oscillations that commence at fields as low as 12T. These oscillations suddenly break into a very large amplitude at 24.8 T implying a Lifshitz transition. Continuing to higher fields these large amplitude oscillations disappear at 30 T beyond which much smaller oscillations with altered frequencies are observed. Magnetostriction measurements performed at fields up to 65 T for θ=90o reveal small features that are consistent with boundaries at similar magnetic field values. Further, the 30 T transition appears to merge with the angle dependent metamagnetic transition at the intermediate angle θ=50o. For field along this unique angle the magnetostriction along c-axis vanishes precisely for all magnetic field values. High resolution magnetization measurements vs. field are, surprisingly, featureless and near linear when θ=90o.

*The work at the University of Virginia was funded by NSF DMR 0073456. The National Magnet Laboratory in Tallahassee and
at Los Alamos is supported by the National Science Foundation and the State of Florida.

–

Presenters

  • Bellave Shivaram

    • University of Virginia

Authors

  • Bellave Shivaram

    • University of Virginia

  • Ludwig Holleis

    • University of Virginia

  • Marcelo Jaime

    • National High Magnetic Field Laboratory, Los Alamos
    • Los Alamos National Laboratory
    • National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545
    • NHMFL, Los Alamos National Labs
    • NHMFL-LANL
    • Pulsed Field Faclity, National High Magnetic Field Laboratory

  • John Singleton

    • National High Magnetic Field Laboratory, Los Alamos National Laboratory
    • MPA-MAG, Los Alamos National Laboratory
    • National High Magnetic Field Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545
    • Los Alamos National Laboratory
    • NHMFL, Los Alamos National Labs
    • NHMFL, Los Alamos National Laboratory
    • Los Alamos, National High Magnetic Field Laboratory
    • NHMFL, Los Alamos Natl Lab
    • Los Alamos Natl Lab

  • Vern Ulrich

    • University of Virginia