Hybridization driven quantum critical behavior in weakly-itinerant ferromagnets

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}.