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arXiv · 1403.1969

Observation of a Zeeman Induced Lifshitz Transition in URu2Si2

B. S. Shivaram·V. W. Ulrich·D. G. Hinks
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Abstract

High resolution longitudinal sound velocity measurements in a magnetic field performed at T tending to zero in URu2Si2 reveal a second signature at a field BLT in addition to the step change in velocity expected at the superconducting upper critical field, Bc2. Characteristic Fermi surface related magneto-acoustic quantum oscillations (MAQO) emerge beyond the field BLT at a frequency ~160 T for B||a-axis. Measurements performed with B oriented at various angles between the a and c-axes reveal an anisotropy for BLT nearly identical to that of BC2 suggesting similarity of the electron states involved in both the transitions. Given the observed frequency of ~160 T in the MAQO the transition is most likely related to the emergence of the \\eta Fermi surface in URu2Si2 (Lifshitz transition).

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B. S. Shivaram, V. W. Ulrich, D. G. Hinks. 2014-03-08. Observation of a Zeeman Induced Lifshitz Transition in URu2Si2. https://arxiv.org/abs/1403.1969

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