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Ground state properties of a Zeeman-split heavy metal

K. S. D. Beach
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Abstract

A Zeeman field affects the metallic heavy fermion ground state in two ways: (i) it splits the spin-degerenate conduction sea, leaving spin up and spin down Fermi surfaces with different band curvature; (ii) it competes with the Kondo effect and thus suppresses the mass enhancement. Taking these two effects into account, we compute the quasiparticle effective mass as a function of applied field strength within hybridization mean field theory. We also derive an expression for the optical conductivity, which is relevant to infrared spectroscopy measurements.

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K. S. D. Beach. 2005-09-29. Ground state properties of a Zeeman-split heavy metal. https://arxiv.org/abs/cond-mat/0509778

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