The dual nature of 5f electrons and origin of heavy fermions in U compounds

G Zwicknagl; P. Fulde

doi:10.1088/0953-8984/15/28/302

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The dual nature of 5f electrons and origin of heavy fermions in U compounds

G Zwicknagl·P. Fulde

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Abstract

We develop a theory for the electronic excitations in UPt$_3$ which is based on the localization of two of the $5f$ electrons. The remaining $f$ electron is delocalized and acquires a large effective mass by inducing intra-atomic excitations of the localized ones. The measured deHaas-vanAlphen frequencies of the heavy quasiparticles are explained as well as their anisotropic heavy mass. A model calculation for a small cluster reveals why only the largest of the different $5f$ hopping matrix elements is operative causing the electrons in other orbitals to localize.

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G Zwicknagl, P. Fulde. 2002-11-29. The dual nature of 5f electrons and origin of heavy fermions in U compounds. https://doi.org/10.1088/0953-8984%2F15%2F28%2F302

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