Multiple regions of quantum criticality in YbAgGe

G. M. Schmiedeshoff; E. D. Mun; A. W. Lounsbury; S. J. Tracy; E. C. Palm; S. T. Hannahs; J. -H. Park; T. P. Murphy; S. L. Bud'ko; P. C. Canfield

doi:10.1103/physrevb.83.180408

arXiv · 1102.4867

Multiple regions of quantum criticality in YbAgGe

G. M. Schmiedeshoff·E. D. Mun·A. W. Lounsbury·S. J. Tracy·E. C. Palm·S. T. Hannahs·J. -H. Park·T. P. Murphy·S. L. Bud'ko·P. C. Canfield

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Abstract

Dilation and thermopower measurements on YbAgGe, a heavy-fermion antiferromagnet, clarify and refine the magnetic field-temperature (H-T) phase diagram and reveal a field-induced phase with T-linear resistivity. On the low-H side of this phase we find evidence for a first-order transition and suggest that YbAgGe at 4.5 T may be close to a quantum critical end point. On the high-H side our results are consistent with a second-order transition suppressed to a quantum critical point near 7.2 T. We discuss these results in light of global phase diagrams proposed for Kondo lattice systems.

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G. M. Schmiedeshoff, E. D. Mun, A. W. Lounsbury, S. J. Tracy, E. C. Palm, S. T. Hannahs, J. -H. Park, T. P. Murphy, S. L. Bud'ko, P. C. Canfield. 2011-02-23. Multiple regions of quantum criticality in YbAgGe. https://doi.org/10.1103/physrevb.83.180408

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