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

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 نشر من قبل Murray Batchelor
 تاريخ النشر 2019
  مجال البحث فيزياء
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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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