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From ferromagnetism to spin-density wave: Magnetism in the two channel periodic Anderson model

Frithjof B. Anders
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Abstract

The magnetic properties of the two-channel periodic Anderson model for uranium ions, comprised of a quadrupolar and a magnetic doublet are investigated through the crossover from the mixed-valent to the stable moment regime using dynamical mean field theory. In the mixed-valent regime ferromagnetism is found for low carrier concentration on a hyper-cubic lattice. The Kondo regime is governed by band magnetism with small effective moments and an ordering vector $\q$ close to the perfect nesting vector. In the stable moment regime nearest neighbour anti-ferromagnetism dominates for less than half band filling and a spin density wave transition for larger than half filling. $T_m$ is governed by the renormalized RKKY energy scale $μ_{eff}^2 ^2 J^2ρ_0(μ)$.

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Frithjof B. Anders. 1999-05-18. From ferromagnetism to spin-density wave: Magnetism in the two channel periodic Anderson model. https://doi.org/10.1103/physrevlett.83.4638

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