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Photoemission spectra of many-polaron systems

M. Hohenadler·D. Neuber·W. von der Linden·G. Wellein·J. Loos·H. Fehske
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Abstract

The cross over from low to high carrier densities in a many-polaron system is studied in the framework of the one-dimensional spinless Holstein model, using unbiased numerical methods. Combining a novel quantum Monte Carlo approach and exact diagonalization, accurate results for the single-particle spectrum and the electronic kinetic energy on fairly large systems are obtained. A detailed investigation of the quality of the Monte Carlo data is presented. In the physically most important adiabatic intermediate electron-phonon coupling regime, for which no analytical results are available, we observe a dissociation of polarons with increasing band filling, leading to normal metallic behavior, while for parameters favoring small polarons, no such density-driven changes occur. The present work points towards the inadequacy of single-polaron theories for a number of polaronic materials such as the manganites.

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M. Hohenadler, D. Neuber, W. von der Linden, G. Wellein, J. Loos, H. Fehske. 2005-04-08. Photoemission spectra of many-polaron systems. https://doi.org/10.1103/physrevb.71.245111

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