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تسجيل مستخدم جديدField induced Lifshitz transition in UPt$_2$Si$_2$: Fermi surface under extreme conditions
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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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