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arXiv · 1408.3425

Role of impact ionization in the thermalization of photo-excited Mott insulators

Philipp Werner·Karsten Held·Martin Eckstein
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Abstract

We study the influence of the pulse energy and fluence on the thermalization of photo-doped Mott insulators. If the Mott gap is smaller than the width of the Hubbard bands, the kinetic energy of individual carriers can be large enough to produce doublon-hole pairs via a process analogous to impact ionization. The thermalization dynamics, which involves an adjustment of the doublon and hole densities, thus changes as a function of the energy of the photo-doped carriers and exhibits two timescales -- a fast relaxation related to impact ionization and a slower timescale associated with higher-order scattering processes. The slow dynamics depends more strongly on the gap size and the photo-doping concentration.

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Philipp Werner, Karsten Held, Martin Eckstein. 2014-08-14. Role of impact ionization in the thermalization of photo-excited Mott insulators. https://doi.org/10.1103/physrevb.90.235102

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