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arXiv · 1707.02411

Optical signatures of exciton-polarons from diagrammatic Monte Carlo

A. S. Mishchenko·G. De Filippis·V. Cataudella·N. Nagaosa·H. Fehske
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Abstract

We study the interplay of electron-electron and electron-phonon interactions in the course of electron-hole bound state formation for gapped solid state systems. Adapting the essentially approximation-free diagrammatic Monte Carlo method for the calculation of the optical response, we discuss the absorption of light in correlated electron-phonon systems for the whole interaction and phonon frequency regimes. The spectral function obtained by analytical continuation from the imaginary-time current-current correlation function demonstrates the dressing of excitons by a phonon cloud when the coupling the lattice degrees of freedom becomes increasingly important, where notable differences show up between the adiabatic and anti-adiabatic cases.

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A. S. Mishchenko, G. De Filippis, V. Cataudella, N. Nagaosa, H. Fehske. 2017-07-08. Optical signatures of exciton-polarons from diagrammatic Monte Carlo. https://doi.org/10.1103/physrevb.97.045141

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