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Optical excitations of Peierls-Mott insulators with bond disorder

J. Rissler·E. Jeckelmann·F. Gebhard
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Abstract

The density-matrix renormalization group (DMRG) is employed to calculate optical properties of the half-filled Hubbard model with nearest-neighbor interactions. In order to model the optical excitations of oligoenes, a Peierls dimerization is included whose strength for the single bonds may fluctuate. Systems with up to 100 electrons are investigated, their wave functions are analyzed, and relevant length-scales for the low-lying optical excitations are identified. The presented approach provides a concise picture for the size dependence of the optical absorption in oligoenes.

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J. Rissler, E. Jeckelmann, F. Gebhard. 2005-07-05. Optical excitations of Peierls-Mott insulators with bond disorder. https://doi.org/10.1088/0953-8984%2F17%2F26%2F009

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