Entanglement spectra of the q-deformed Affleck-Kennedy-Lieb-Tasaki model and matrix product states

  title={Entanglement spectra of the q-deformed Affleck-Kennedy-Lieb-Tasaki model and matrix product states},
  author={Raul A Santos and Francis N. C. Paraan and Vladimir E. Korepin and Andreas Klumper},
We exactly calculate the reduced density matrix of matrix product states (MPS). Our compact result enables one to perform analytic studies of entanglement in MPS. In particular, we consider the MPS ground states of two anisotropic spin chains. One is a q-deformed Affleck-Kennedy-Lieb-Tasaki (AKLT) model and the other is a general spin-1 quantum antiferromagnet with nearest-neighbor interactions. Our analysis shows how anisotropy affects entanglement on different continuous parameter manifolds… Expand
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