Unified structure for exact towers of scar states in the Affleck-Kennedy-Lieb-Tasaki and other models

  title={Unified structure for exact towers of scar states in the Affleck-Kennedy-Lieb-Tasaki and other models},
  author={Daniel K. Mark and Cheng-Ju Lin and Olexei I. Motrunich},
  journal={Physical Review B},
Quantum many-body scar states are many-body states with finite energy density in non-integrable models that do not obey the eigenstate thermalization hypothesis. Recent works have revealed “towers” of scar states that are exactly known and are equally spaced in energy, specifically in the AKLT and spin-1 XY models, and a spin-1/2 model that conserves the number of domain walls. We provide a common framework to understand and prove known exact towers of scars in these systems, by evaluating the… 

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