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arXiv · 1612.02617

Energy spectrum and critical exponents of the free parafermion $Z_N$ spin chain

Francisco C Alcaraz·Murray T Batchelor·Zi-Zhong Liu
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Abstract

Results are given for the ground state energy and excitation spectrum of a simple $N$-state $Z_N$ spin chain described by free parafermions. The model is non-Hermitian for $N \ge 3$ with a real ground state energy and a complex excitation spectrum. Although having a simpler Hamiltonian than the superintegrable chiral Potts model, the model is seen to share some properties with it, e.g., the specific heat exponent $α=1-2/N$ and the anisotropic correlation length exponents $ν_\parallel =1$ and $ν_\perp=2/N$.

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Francisco C Alcaraz, Murray T Batchelor, Zi-Zhong Liu. 2017-02-27. Energy spectrum and critical exponents of the free parafermion $Z_N$ spin chain. https://doi.org/10.1088/1751-8121%2Faa645a

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