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arXiv · 1107.0816

Evolution toward Quantum Critical End Point in UGe_2

Hisashi Kotegawa·Valentin Taufour·Dai Aoki·Georg Knebel·Jacques Flouquet
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Abstract

We report on Hall resistivity and electrical resistivity measurements under pressure and magnetic field in UGe_2 with ferromagnetic (FM) tricriticality. The Hall resistivity sensitively detects the first order metamagnetic transition from a paramagnetic (PM) phase to a FM phase in a large pressure range almost up to the quantum critical end point (QCEP). The drastic change in the Fermi surface at the PM-FM transition is detected up to the vicinity of the QCEP, while a strong modification in the field variation of the inelastic scattering between electrons is observed toward the QCEP. The comparison with the theoretical predictions is made.

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Hisashi Kotegawa, Valentin Taufour, Dai Aoki, Georg Knebel, Jacques Flouquet. 2011-07-05. Evolution toward Quantum Critical End Point in UGe_2. https://doi.org/10.1143/jpsj.80.083703

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