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Strong coupling in the Kondo problem in the low-temperature region

Yu. N. Ovchinnikov·A. M. Dyugaev
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Abstract

The magnetic field dependence of the average spin of a localized electron coupled to conduction electrons with an antiferromagnetic exchange interaction is found for the ground state. In the magnetic field range $μH\sim 0.5 T_c$ ($T_c$ is the Kondo temperature) there is an inflection point, and in the strong magnetic field range $μH\gg T_c$, the correction to the average spin is proportional to $(T_c/μH)^2$. In zero magnetic field, the interaction with conduction electrons also leads to the splitting of doubly degenerate spin impurity states.

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Yu. N. Ovchinnikov, A. M. Dyugaev. 1999-01-17. Strong coupling in the Kondo problem in the low-temperature region. https://doi.org/10.1134/1.558846

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