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arXiv · 1610.01212

Field induced Lifshitz transition in UPt$_2$Si$_2$: Fermi surface under extreme conditions

D. Schulze Grachtrup·N. Steinki·S. Süllow·Z. Cakir·G. Zwicknagl·Y. Krupko·I. Sheikin·M. Jaime·J. A. Mydosh
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Abstract

We have measured Hall effect, magnetotransport and magnetostriction on the field induced phases of single crystalline UPt$_2$Si$_2$ in magnetic fields up to 60\,T at temperatures down to 50\,mK. For the magnetic field applied along the $c$ axis we observe strong changes in the Hall effect at the phase boundaries. From a comparison to band structure calculations utilizing the concept of a dual nature of the uranium 5$f$ electrons, we find evidence for field induced topological changes of the Fermi surface due to at least one Lifshitz transition. Furthermore, we find a unique history dependence of the magnetotransport and magnetostriction data, indicating that the Lifshitz type transition is of a discontinuous nature, as predicted for interacting electron systems.

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D. Schulze Grachtrup, N. Steinki, S. Süllow, Z. Cakir, G. Zwicknagl, Y. Krupko, I. Sheikin, M. Jaime, J. A. Mydosh. 2017-03-06. Field induced Lifshitz transition in UPt$_2$Si$_2$: Fermi surface under extreme conditions. https://doi.org/10.1103/physrevb.95.134422

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