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arXiv · 1104.2287

Hybridization driven quantum critical behavior in weakly-itinerant ferromagnets

M. B. Silva Neto·A. H. Castro Neto·J. S. Kim·G. R. Stewart
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Abstract

We investigate the unusual magnetic properties of nearly-critical, weakly-itinerant ferromagnets with general formula UTX, where T=Rh,Co and X=Ge,Si. As a unique feature about these systems, we show that changes in the V_{df} hybridization control their proximity to a ferromagnetic instability, and determine the evolution of: the ground state magnetization, M_0, the Curie Temperature, T_C, the density of states at the Fermi level, N(E_F), the T^2 resistivity coefficient, A, and the specific heat coefficient, \gamma. The universal aspect of our findings comes from the dependence on only two parameters: the T_d bandwidth, W_d, and the distance between T_d and U_f band centers, C_{T_d}-C_{U_f}.

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M. B. Silva Neto, A. H. Castro Neto, J. S. Kim, G. R. Stewart. 2011-04-12. Hybridization driven quantum critical behavior in weakly-itinerant ferromagnets. https://arxiv.org/abs/1104.2287

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