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Critical local-moment fluctuations, anomalous exponents, and omega/T scaling in the Kondo problem with a pseudogap

Kevin Ingersent·Qimiao Si
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Abstract

Experiments in heavy-fermion metals and related theoretical work suggest that critical local-moment fluctuations can play an important role near a zero-temperature phase transition. We study such fluctuations at the quantum critical point of a Kondo impurity model in which the density of band states vanishes as |E|^r at the Fermi energy (E = 0). The local spin response is described by a set of critical exponents that vary continuously with r. For 0 < r < 1, the dynamical susceptibility exhibits omega/T scaling with a fractional exponent, implying that the critical point is interacting.

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Kevin Ingersent, Qimiao Si. 2002-07-25. Critical local-moment fluctuations, anomalous exponents, and omega/T scaling in the Kondo problem with a pseudogap. https://doi.org/10.1103/physrevlett.89.076403

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