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arXiv · 1004.0107

Evidence for a Non-Fermi-Liquid Phase in Ge-Substituted YbRh2Si2

J. Custers·P. Gegenwart·C. Geibel·F. Steglich·P. Coleman·S. Paschen
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Abstract

The canonical view of heavy fermion quantum criticality assumes a single quantum critical point separating the paramagnet from the antiferromagnet. However, recent experiments on Yb-based heavy fermion compounds suggest the presence of non-Fermi liquid behavior over a finite zero-temperature region. Using detailed susceptibility and transport measurements we show that the classic quantum critical system, Ge-substituted YbRh2Si2, also displays such behavior. We advance arguments that this is not due to a disorder-smeared quantum critical point, but represents a new class of metallic phase.

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J. Custers, P. Gegenwart, C. Geibel, F. Steglich, P. Coleman, S. Paschen. 2010-04-01. Evidence for a Non-Fermi-Liquid Phase in Ge-Substituted YbRh2Si2. https://doi.org/10.1103/physrevlett.104.186402

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