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Logarithmic Corrections in Quantum Impurity Problems

Ian Affleck·Shaojin Qin
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Abstract

The effect of a BULK marginal operator on BOUNDARY critical phenomena in two space-time dimensions is considered. The particular case of an open S=1/2 antiferromagnetic Heisenberg chain, corresponding to a Wess-Zumino-Witten non-linear sigma model, is solved. In this case, the needed renormalization group coefficient is associated with a novel operator product expansion in which THREE operators approach the same point. Resulting logarithmic corrections occurring in finite size calculations and nuclear magnetic resonance experiments are discussed.

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Ian Affleck, Shaojin Qin. 1999-07-23. Logarithmic Corrections in Quantum Impurity Problems. https://doi.org/10.1088/0305-4470%2F32%2F45%2F301

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