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arXiv · 1901.06439

Conformal fields and operator product expansion in critical quantum spin chains

Yijian Zou·Ashley Milsted·Guifre Vidal
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Abstract

We propose a variational method for identifying lattice operators in a critical quantum spin chain with scaling operators in the underlying conformal field theory (CFT). In particular, this allows us to build a lattice version of the primary operators of the CFT, from which we can numerically estimate the operator product expansion coefficients $C_{αβγ}^{\textrm{ CFT}}$. We demonstrate the approach with the critical Ising quantum spin chain.

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Yijian Zou, Ashley Milsted, Guifre Vidal. 2019-01-18. Conformal fields and operator product expansion in critical quantum spin chains. https://doi.org/10.1103/physrevlett.124.040604

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