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arXiv · 2007.16035

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

Anna Kauch·Paul Worm·Paul Prauhart·Michael Innerberger·Clemens Watzenböck·Karsten Held
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Abstract

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-nearest neighbor hopping to the model leads to a significant enhancement of impact ionization, as does disorder and geometric frustration of a triangular lattice.

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Anna Kauch, Paul Worm, Paul Prauhart, Michael Innerberger, Clemens Watzenböck, Karsten Held. 2020-07-31. Enhancement of impact ionization in Hubbard clusters by disorder and next-nearest-neighbor hopping. https://doi.org/10.1103/physrevb.102.245125

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