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Behavior of magnetic impurities in gapless Fermi systems

Kevin Ingersent
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Abstract

In a number of systems, including certain semiconductors and unconventional superconductors, the effective density of states varies near the Fermi energy like $|E-E_F|^r$. The behavior of dilute magnetic impurities in such systems is studied using a non-perturbative renormalization-group approach. Close to particle-hole symmetry, the Kondo effect is suppressed for the cases of greatest relevance ($r=1$ and $2$). Away from this symmetry, any quenching of the impurity moment is accompanied by a low-temperature decrease in the impurity resistivity, rather than the increase found in metals.

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Kevin Ingersent. 1996-05-13. Behavior of magnetic impurities in gapless Fermi systems. https://doi.org/10.1103/physrevb.54.11936

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