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Locally critical point in an anisotropic Kondo lattice

D. R. Grempel·Qimiao Si
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Abstract

We report the first numerical identification of a locally quantum critical point, at which the criticality of the local Kondo physics is embedded in that associated with a magnetic ordering. We are able to numerically access the quantum critical behavior by focusing on a Kondo-lattice model with Ising anisotropy. We also establish that the critical exponent for the q-dependent dynamical spin susceptibility is fractional and compares well with the experimental value for heavy fermions.

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D. R. Grempel, Qimiao Si. 2003-07-21. Locally critical point in an anisotropic Kondo lattice. https://doi.org/10.1103/physrevlett.91.026401

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