Onsager's Scars in Disordered Spin Chains.

@article{Shibata2019OnsagersSI,
  title={Onsager's Scars in Disordered Spin Chains.},
  author={Naoyuki Shibata and Nobuyuki Yoshioka and Hosho Katsura},
  journal={Physical review letters},
  year={2019},
  volume={124 18},
  pages={
          180604
        }
}
We propose a class of nonintegrable quantum spin chains that exhibit quantum many-body scars even in the presence of disorder. With the use of the so-called Onsager symmetry, we construct scarred models for arbitrary spin quantum number S. There are two types of scar states, namely, coherent states associated with an Onsager-algebra element and one-magnon scar states. While both of them are highly excited states, they have area-law entanglement and can be written as a matrix product state… 

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