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Optical conductivity of polaronic charge carriers

Jan Loos·Martin Hohenadler·Andreas Alvermann·Holger Fehske
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Abstract

The optical conductivity of charge carriers coupled to quantum phonons is studied in the framework of the one-dimensional spinless Holstein model. For one electron, variational diagonalisation yields exact results in the thermodynamic limit, whereas at finite carrier density analytical approximations based on previous work on single-particle spectral functions are obtained. Particular emphasis is put on deviations from weak-coupling, small-polaron or one-electron theories occurring at intermediate coupling and/or finite carrier density. The analytical results are in surprisingly good agreement with exact data, and exhibit the characteristic polaronic excitations observed in experiments on manganites.

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Jan Loos, Martin Hohenadler, Andreas Alvermann, Holger Fehske. 2007-06-01. Optical conductivity of polaronic charge carriers. https://doi.org/10.1088/0953-8984%2F19%2F23%2F236233

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