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Entanglement used to identify critical systems

S. O. Skrøvseth·K. Olaussen
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Abstract

We promote use of the geometric entropy formula derived by Holzhey et. al. from conformal field theory, $S_\ell\sim ({c}/{3}) \log(\sin{π\ell}/{N})$, to identify critical regions in zero temperature 1D quantum systems. The method is demonstrated on a class of one-dimensional XY and $XYZ$ spin-1/2 chains, where the critical regions and their correponding central charges can be reproduced with quite modest computational efforts.

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BibTeXRIS

S. O. Skrøvseth, K. Olaussen. 2005-08-15. Entanglement used to identify critical systems. https://doi.org/10.1103/physreva.72.022318

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