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arXiv · 0802.3965

Enhancement of phonon effects in photoexcited states of one-dimensional Mott insulators

Hiroaki Matsueda·Akihiro Ando·Takami Tohyama·Sadamichi Maekawa
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Abstract

We examine how the electron correlation affects the electron-phonon (EP) interaction in the linear optical absorption spectrum of the one-dimensional (1D) extended Hubbard-Holstein model. A density matrix renormalization group (DMRG) calculation shows that the effect of the EP interaction on an exciton is enhanced by increasing the on-site Coulomb repulsion. This enhancement is in contrast to the effect of the EP interaction on the ground state where the Peierls instability is suppressed by the on-site Coulomb repulsion. The DMRG data with the EP interaction fit with absorption experiments in 1D cuprates better than those for the extended Hubbard model.

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Hiroaki Matsueda, Akihiro Ando, Takami Tohyama, Sadamichi Maekawa. 2008-02-27. Enhancement of phonon effects in photoexcited states of one-dimensional Mott insulators. https://doi.org/10.1103/physrevb.77.193112

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