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arXiv · 1206.6223

New Universality Class of Quantum Criticality in Ce- and Yb-based Heavy Fermions

Shinji Watanabe·Kazumasa Miyake
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Abstract

A new universality class of quantum criticality emerging in itinerant electron systems with strong local electron correlations is discussed. The quantum criticality of a Ce- or Yb-valence transition gives us a unified explanation for unconventional criticality commonly observed in heavy fermion metals such as YbRh2Si2 and β-YbAlB4, YbCu5-xAlx, and CeIrIn5. The key origin is due to the locality of the critical valence fluctuation mode emerging near the quantum critical end point of the first-order valence transition, which is caused by strong electron correlations for f electrons. Wider relevance of this new criticality and important future measurements to uncover its origin are also discussed.

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Shinji Watanabe, Kazumasa Miyake. 2012-06-27. New Universality Class of Quantum Criticality in Ce- and Yb-based Heavy Fermions. https://doi.org/10.1088/0953-8984%2F24%2F29%2F294208

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