English

The Fisher-Hartwig Formula and Generalized Entropies in XY Spin Chain

Mathematical Physics 2009-12-19 v4 Statistical Mechanics math.MP Quantum Physics

Abstract

Toeplitz matrices have applications to different problems of statistical mechanics. Recently they were used for calculation of entanglement entropy in spin chains. We use the Fisher-Hartwig formula to calculate entanglement entropy of large block of spins in the ground state of XY spin chain. We also calculate Renyi entropy and prove that the spectrum of the density matrix of a block of spins is exact geometric sequence [also different eigenvalues are degenerated differently].

Keywords

Cite

@article{arxiv.0906.4511,
  title  = {The Fisher-Hartwig Formula and Generalized Entropies in XY Spin Chain},
  author = {A. R. Its and V. E. Korepin},
  journal= {arXiv preprint arXiv:0906.4511},
  year   = {2009}
}

Comments

29 page, 2 figures