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arXiv · 2010.15797

Broadening and sharpening of the Drude peak through antiferromagnetic fluctuations

Paul Worm·Clemens Watzenböck·Matthias Pickem·Anna Kauch·Karsten Held
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Abstract

Antiferromagnetic or charge density wave fluctuations couple with light through the recently discovered π-ton contribution to the optical conductivity, and quite generically constitute the dominant vertex corrections in low-dimensional correlated electron systems. Here we study the arguably simplest version of these $π$-tons based on the semi-analytical random phase approximation (RPA) ladder in the transversal particle-hole channel. The vertex corrections to the optical conductivity are calculated directly for real frequencies. We validate that the RPA qualitatively reproduces the π-ton vertex corrections to the Drude peak in the Hubbard model. Depending on the temperature we find vertex corrections to broaden or sharpen the Drude peak.

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Paul Worm, Clemens Watzenböck, Matthias Pickem, Anna Kauch, Karsten Held. 2021-08-31. Broadening and sharpening of the Drude peak through antiferromagnetic fluctuations. https://doi.org/10.1103/physrevb.104.115153

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