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arXiv · 0710.3260

YbRh2Si2: Quantum tricritical behavior in itinerant electron systems

Takahiro Misawa·Youhei Yamaji·Masatoshi Imada
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Abstract

We propose that proximity of the first-order transition manifested by the quantum tricritical point (QTCP) explains non-Fermi-liquid properties of YbRh2Si2. Here, at the QTCP, a continuous phase transition changes into first order at zero temperature. The non-Fermi-liquid behaviors of YbRh2Si2 are puzzling in two aspects; diverging ferromagnetic susceptibility at the antiferromagnetic transition and unconventional power-law dependence in thermodynamic quantities. These puzzles are solved by an unconventional criticality derived from our spin fluctuation theory for the QTCP.

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Takahiro Misawa, Youhei Yamaji, Masatoshi Imada. 2008-04-24. YbRh2Si2: Quantum tricritical behavior in itinerant electron systems. https://doi.org/10.1143/jpsj.77.093712

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