Multiple regions of quantum criticality in YbAgGe

TitleMultiple regions of quantum criticality in YbAgGe
Publication TypeJournal Article
Year of Publication2011
AuthorsSchmiedeshoff GM, Mun ED, Lounsbury AW, Tracy SJ, Palm EC, Hannahs ST, Park JH, Murphy TP, Bud'ko SL, Canfield PC
Journal TitlePhysical Review B
Date Published05
ISBN Number1098-0121
Accession NumberWOS:000293333600004

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.