# 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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