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arXiv · 0903.3821

Possible Phase Transition Deep Inside the Hidden Order Phase of Ultraclean URu2Si2

H. Shishido·K. Hashimoto·T. Shibauchi·T. Sasaki·H. Oizumi·N. Kobayashi·T. Takamasu·K. Takehana·Y. Imanaka·T. D. Matsuda·Y. Haga·Y. Onuki·Y. Matsuda
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Abstract

To elucidate the underlying nature of the hidden order (HO) state in heavy-fermion compound URu2Si2, we measure electrical transport properties of ultraclean crystals in a high field/low temperature regime. Unlike previous studies, the present system with much less impurity scattering resolves a distinct anomaly of the Hall resistivity at H*=22.5 T well below the destruction field of the HO phase ~36 T. In addition, a novel quantum oscillation appears above a magnetic field slightly below H*. These results indicate an abrupt reconstruction of the Fermi surface, which implies a possible phase transition well within the HO phase caused by a band-dependent destruction of the HO parameter. The present results definitely indicate that the HO transition should be described by an itinerant electron picture.

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H. Shishido, K. Hashimoto, T. Shibauchi, T. Sasaki, H. Oizumi, N. Kobayashi, T. Takamasu, K. Takehana, Y. Imanaka, T. D. Matsuda, Y. Haga, Y. Onuki, Y. Matsuda. 2009-03-23. Possible Phase Transition Deep Inside the Hidden Order Phase of Ultraclean URu2Si2. https://doi.org/10.1103/physrevlett.102.156403

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