Statistical properties of the off-diagonal matrix elements of observables in eigenstates of integrable systems.

@article{Zhang2022StatisticalPO,
  title={Statistical properties of the off-diagonal matrix elements of observables in eigenstates of integrable systems.},
  author={Yicheng Zhang and Lev Vidmar and Marcos Rigol},
  journal={Physical review. E},
  year={2022},
  volume={106 1-1},
  pages={
          014132
        }
}
We study the statistical properties of the off-diagonal matrix elements of observables in the energy eigenstates of integrable quantum systems. They have been found to be dense in the spin-1/2 XXZ chain, while they are sparse in noninteracting systems. We focus on the quasimomentum occupation of hard-core bosons in one dimension and show that the distributions of the off-diagonal matrix elements are well described by generalized Gamma distributions, in both the presence and absence of… 
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