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arXiv · 1905.08384

Some ground-state expectation values for the free parafermion Z(N) spin chain

Zi-Zhong Liu·Robert A. Henry·Murray T. Batchelor·Huan-Qiang Zhou
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Abstract

We consider the calculation of ground-state expectation values for the non-Hermitian Z(N) spin chain described by free parafermions. For N=2 the model reduces to the quantum Ising chain in a transverse field with open boundary conditions. Use is made of the Hellmann-Feynman theorem to obtain exact results for particular single site and nearest-neighbour ground-state expectation values for general N which are valid for sites deep inside the chain. These results are tested numerically for N=3, along with how they change as a function of distance from the boundary.

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Zi-Zhong Liu, Robert A. Henry, Murray T. Batchelor, Huan-Qiang Zhou. 2019-10-14. Some ground-state expectation values for the free parafermion Z(N) spin chain. https://doi.org/10.1088/1742-5468%2Fab4fe1

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