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A two-channel Kondo impurity in the spin-1/2 chain: Consequences for Knight shift experiments

Sebastian Eggert·Stefan Rommer
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Abstract

A magnetic impurity in the spin-1/2 chain is a simple realization of the two-channel Kondo problem since the field theoretical descriptions in the spin-sector are identical. The correlation functions near the impurity can be calculated. Using a modified version of the numerical transfer matrix DMRG, we are able to accurately determine local properties close to the impurity in the thermodynamic limit. The local susceptibilities (Knight-shifts) show an interesting behavior in a large range around the impurities. We are able to make quantitative experimental predictions which would allow to observe two-channel Kondo physics for the first time directly by doping of spin-1/2 chain compounds.

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Sebastian Eggert, Stefan Rommer. 1998-11-04. A two-channel Kondo impurity in the spin-1/2 chain: Consequences for Knight shift experiments. https://doi.org/10.1016/s0921-4526(98)01029-1

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