Enhancement of impact ionization in Hubbard clusters by disorder and next-nearest-neighbor hopping

  title={Enhancement of impact ionization in Hubbard clusters by disorder and next-nearest-neighbor hopping},
  author={Anna Kauch and Paul Worm and Paul Prauhart and Michael Innerberger and Clemens Watzenb{\"o}ck and Karsten Held},
  journal={Physical Review B},
We perform time-resolved exact diagonalization of the Hubbard model with time dependent hoppings on small clusters of up to $12$ sites. Here, the time dependence originates from a classic electromagnetic pulse, which mimics the impact of a photon. We investigate the behavior of the double occupation and spectral function after the pulse for different cluster geometries and on-site potentials. We find impact ionization in all studied geometries except for one-dimensional chains. Adding next… 

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