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arXiv · 1911.09907

Boundary conformal spectrum and surface critical behaviors of the classical spin systems: a tensor network renormalization study

Abstract

We numerically obtain the conformal spectrum of several classical spin models on a two-dimensional lattice with open boundaries, for every boundary fixed point obtained by the Cardy's derivation [J. L. Cardy, Nucl. Phys. B 324, 581 (1989)]. In order to extract accurate conformal data, we implement the tensor network renormalization algorithm [G. Evenbly and G. Vidal, Phys. Rev. Lett. 115, 180405 (2015)] extended so as to be applicable to a square lattice with open boundaries. We successfully compute the boundary conformal spectrum consistent with the underlying boundary conformal field theories (BCFTs) for the Ising, tri-critical Ising, and 3-state Potts models on the lattice, which allows us to confirm the validity of the BCFT analyses for the surface critical behaviors of those lattice models.

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Shumpei Iino, Satoshi Morita, Naoki Kawashima. 2020-03-14. Boundary conformal spectrum and surface critical behaviors of the classical spin systems: a tensor network renormalization study. https://doi.org/10.1103/physrevb.101.155418

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