title: d-f hybridization and quantum criticality in weakly-itinerant ferromagnets.
abstract: We investigate the unusual magnetic, thermodynamic and transport properties of nearly-critical, weakly-itinerant ferromagnets with the general formula UTX, where T=Rh, Co and X=Ge, Si. As a unique feature of these systems, we show how changes in the V(df) hybridization, which controls their proximity to a ferromagnetic instability, 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, γ. The universal aspect of our findings comes from the dependence on only two parameters: the transition metal T(d) bandwidth, W(d), and the distance between the T(d) and U(f) band centers, C(T(d)) - C(U(f)). We discuss our results in connection to data for URh(1-x)Co(x)Ge.
authors.affiliation: Instituto de Fisica, Universidade Federal do Rio de Janeiro, Brazil. mbsn@if.ufrj.br
authors.forename: M B
authors.initials: MB
authors.lastname: Silva Neto
authors.forename: A H
authors.initials: AH
authors.lastname: Castro Neto
authors.forename: J S
authors.initials: JS
authors.lastname: Kim
authors.forename: G R
authors.initials: GR
authors.lastname: Stewart
mesh_terms: D003198:Computer Simulation; D007501:Iron / Q000737:chemistry*; D060526:Magnetic Fields; D059346:Magnets; D008956:Models, Chemical; D008958:Models, Molecular; D011789:Quantum Theory; D013696:Temperature
chemical_list: D007501:Iron