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Scaling and universality in the anisotropic Kondo model and the dissipative two-state system

T. A. Costi
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Abstract

Scaling and universality in the Ohmic two-state system is investigated by exploiting the equivalence of this model to the anisotropic Kondo model. For the Ohmic two-state system, we find universal scaling functions for the specific heat, $C_α(T)$, static susceptibility, $χ_α(T)$, and spin relaxation function $S_α(ω)$ depending on the reduced temperature $T/Δ_{r}$ (frequency $ω/Δ_{r}$), with $Δ_{r}$ the renormalized tunneling frequency, and uniquely specified by the dissipation strength $α$ ($0<α<1$). The scaling functions can be used to extract $α$ and $Δ_{r}$ in experimental realizations.

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T. A. Costi. 1998-01-21. Scaling and universality in the anisotropic Kondo model and the dissipative two-state system. https://doi.org/10.1103/physrevlett.80.1038

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