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arXiv · 0806.2083

Bound Excitons in Sr$_{2}$CuO$_{3}$

K. W. Kim·G. D. Gu·C. C. Homes·T. W. Noh
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Abstract

We investigated temperature dependent optical spectra of the one-dimensional chain compound Sr$_{2}$CuO$_{3}$. The charge transfer transition polarized along the chain direction shows a strongly asymmetric line shape as expected in one-dimensional extended Hubbard model. At low temperature the charge transfer peak shows a large blue shift and reveals additional sharp peaks at the gap. Even though many spectroscopic studies suggest that this material can not have a bound exciton based on the one-dimensional extended Hubbard model, we attribute the additional sharp peaks to excitons, which come to exist due to the long range Coulomb interaction.

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K. W. Kim, G. D. Gu, C. C. Homes, T. W. Noh. 2008-10-26. Bound Excitons in Sr$_{2}$CuO$_{3}$. https://doi.org/10.1103/physrevlett.101.177404

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