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The XX-model with boundaries. Part II: Finite size scaling and partition functions

Ulrich Bilstein
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Abstract

We compute the continuum limit of the spectra for the XX-model with arbitrary complex boundary fields. In the case of hermitian boundary terms one obtains the partition functions of the free compactified boson field on a cylinder with Neumann-Neumann, Dirichlet-Neumann or Dirichlet-Dirichlet boundary conditions. This applies also for certain non-hermitian boundaries. For special cases we also compute the free surface energy. For certain non-hermitian boundary terms the results are more complex.Here one obtains logarithmic corrections to the free surface energy. The asymmetric version of the XX-model with boundaries (this includes the Dzyaloshinsky-Moriya interaction)is also discussed.

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Ulrich Bilstein. 2000-02-10. The XX-model with boundaries. Part II: Finite size scaling and partition functions. https://doi.org/10.1088/0305-4470%2F33%2F24%2F303

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