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Infrared conductivity of a one-dimensional charge-ordered state: quantum lattice effects

C. A. Perroni·V. Cataudella·G. De Filippis·G. Iadonisi·V. Marigliano Ramaglia·F. Ventriglia
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Abstract

The optical properties of the charge-ordering ($CO$) phase of the one-dimensional (1D) half-filled spinless Holstein model are derived at zero temperature within a well-known variational approach improved including second-order lattice fluctuations. Within the $CO$ phase, the static lattice distortions give rise to the optical interband gap, that broadens as the strength of the electron-phonon ($el-ph$) interaction increases. The lattice fluctuation effects induce a long subgap tail in the infrared conductivity and a wide band above the gap energy. The first term is due to the multi-phonon emission by the charge carriers, the second to the interband transitions accompanied by the multi-phonon scattering. The results show a good agreement with experimental spectra.

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C. A. Perroni, V. Cataudella, G. De Filippis, G. Iadonisi, V. Marigliano Ramaglia, F. Ventriglia. 2003-02-06. Infrared conductivity of a one-dimensional charge-ordered state: quantum lattice effects. https://doi.org/10.1103/physrevb.67.214301

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