Instituto de Fisica, Universidade Federal do Rio de Janeiro, Brazil.
J Phys Condens Matter. 2013 Jan 16;25(2):025601. doi: 10.1088/0953-8984/25/2/025601. Epub 2012 Dec 4.
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.
我们研究了具有通式 UTX 的近临界、弱巡游亚铁磁体的异常磁、热力学和输运性质，其中 T=Rh、Co 和 X=Ge、Si。作为这些系统的一个独特特征，我们展示了控制它们接近铁磁不稳定性的 V(df)杂化的变化如何决定基态磁化强度 M(0)、居里温度 T(C)、费米能级处的态密度 N(E(F))、T(2)电阻率系数 A 和比热系数 γ 的演化。我们研究结果的普遍性源于仅依赖于两个参数：过渡金属 T(d)带宽 W(d)和 T(d)与 U(f)带中心之间的距离 C(T(d))-C(U(f))。我们将我们的结果与 URh(1-x)Co(x)Ge 的数据进行了讨论。
