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Low energy properties of M-state tunneling systems in metals: New candidates for non-Fermi-liquid systems

G. Zaránd
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Abstract

We construct a generalized multiplicative renormalization group transformation to study the low energy dynamics of a heavy particle tunneling among $M$ different positions and interacting with $N_f$ independent conduction electron channels. Using a $1/N_f$-expansion we show that this M-level scales towards a fixed point equivalent to the $N_f$ channel $SU(M) \times SU(N_f)$ Coqblin-Schrieffer model. Solving numerically the scaling equations we find that a realistic M-level system scales close to this fixed point (FP) and its Kondo temperature is in the experimentally observable range $1-10 K$.

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G. Zaránd. 1996-10-04. Low energy properties of M-state tunneling systems in metals: New candidates for non-Fermi-liquid systems. https://doi.org/10.1103/physrevlett.77.3609

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