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arXiv · 0810.1791

Novel Quantum Criticality in CeRu$_2$Si$_2$ near Absolute Zero Observed by Thermal Expansion and Magnetostriction

J. Yoshida·S. Abe·D. Takahashi·Y. Segawa·Y. Komai·H. Tsujii·K. Matsumoto·H. Suzuki·Y. Ōnuki
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Abstract

We report linear thermal expansion and magnetostriction measurements for CeRu$_2$Si$_2$ in magnetic fields up to 52.6 mT and at temperatures down to 1 mK. At high temperatures, this compound showed Landau-Fermi-liquid behavior: The linear thermal expansion coefficient and the magnetostriction coefficient were proportional to the temperature and magnetic field, respectively. In contrast, a pronounced non-Fermi-liquid effect was found below 50 mK. The negative contribution of thermal expansion and magnetostriction suggests the existence of an additional quantum critical point.

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J. Yoshida, S. Abe, D. Takahashi, Y. Segawa, Y. Komai, H. Tsujii, K. Matsumoto, H. Suzuki, Y. Ōnuki. 2008-12-19. Novel Quantum Criticality in CeRu$_2$Si$_2$ near Absolute Zero Observed by Thermal Expansion and Magnetostriction. https://doi.org/10.1103/physrevlett.101.256402

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