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Mixed moment wave function for magnetic heavy fermion compounds

Yunkyu Bang
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Abstract

We propose a variational wave function for the ground state of the magnetic heavy fermion (HF) systems, in which both the Kondo and the RKKY interactions are variationally incorporated and the local f-orbital state exists as a linear combination of a full local moment state and a fully compensated state (mixed moment state). We describe the mechanism for the mixed moment ground state based on the large-N treatment of the Kondo lattice Hamiltonian added with RKKY interaction. With the mixed moment ground state we can explain several puzzling experiments in magnetic HF compounds such as a small value of local moment, coexistence of the antiferromagnetic (AFM) and the paramagnetic (PM) phases, local quantum criticality, etc.

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Yunkyu Bang. 2003-04-22. Mixed moment wave function for magnetic heavy fermion compounds. https://arxiv.org/abs/cond-mat/0206247

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