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arXiv · 1211.3236

Ultrafast charge recombination in photoexcited Mott-Hubbard insulator

Zala Lenarčič·Peter Prelovšek
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Abstract

We present a calculation of the recombination rate of the excited holon-doublon pairs based on the two-dimensional model relevant for undoped cuprates which shows that fast processes, observed in pump-probe experiments on Mott-Hubbard insulators in picosecond range, can be explained even quantitatively with the multi-magnon emission. The precondition is the existence of the Mott-Hubbard bound exciton of the s-type. We find that its decay is exponentially dependent on the Mott-Hubbard gap and on the magnon energy, with a small prefactor which can be traced back to strong correlations and consequently large exciton-magnon coupling.

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Zala Lenarčič, Peter Prelovšek. 2012-11-14. Ultrafast charge recombination in photoexcited Mott-Hubbard insulator. https://doi.org/10.1103/physrevlett.111.016401

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