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arXiv · 1805.05006

Crossover of Correlation Functions near a Quantum Impurity in a Tomonaga-Luttinger Liquid

Chung-Yu Lo·Yoshiki Fukusumi·Masaki Oshikawa·Ying-Jer Kao·Pochung Chen
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Abstract

An impurity in a Tomonaga-Luttinger liquid leads to a crossover between short- and long-distance regime which describes many physical phenomena. However, calculation of the entire crossover of correlation functions over different length scales has been difficult. We develop a powerful numerical method based on infinite DMRG utilizing a finite system with infinite boundary conditions, which can be applied to correlation functions near an impurity. For the $S=1/2$ chain, we demonstrate that the full crossover can be precisely obtained, and that their limiting behaviors show a good agreement with field-theory predictions.

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Chung-Yu Lo, Yoshiki Fukusumi, Masaki Oshikawa, Ying-Jer Kao, Pochung Chen. 2018-05-15. Crossover of Correlation Functions near a Quantum Impurity in a Tomonaga-Luttinger Liquid. https://doi.org/10.1103/physrevb.99.121103

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