Exact scaling functions of the multichannel Kondo model

Serge Florens

doi:10.1103/physrevb.69.113103

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Exact scaling functions of the multichannel Kondo model

Serge Florens

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Abstract

We reinvestigate the large degeneracy solution of the multichannel Kondo problem, and show how in the universal regime the complicated integral equations simplifying the problem can be mapped onto a first order differential equation. This leads to an explicit expression for the full zero-temperature scaling functions at - and away from - the intermediate non Fermi Liquid fixed point, providing complete analytic information on the universal low - and intermediate - energy properties of the model. These results also apply to the widely-used Non Crossing Approximation of the Anderson model, taken in the Kondo regime. An extension of this formalism for studying finite temperature effects is also proposed and offers a simple approach to solve models of strongly correlated electrons with relevance to the physics of heavy fermion compounds.

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Serge Florens. 2003-12-15. Exact scaling functions of the multichannel Kondo model. https://doi.org/10.1103/physrevb.69.113103

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