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arXiv · 2410.23791

Electron-mediated anharmonicity and its role in the Raman spectrum of graphene

Nina Girotto Erhardt·Aloïs Castellano·J. P. Alvarinhas Batista·Raffaello Bianco·Ivor Lončarić·Matthieu J. Verstraete·Dino Novko
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Abstract

The Raman active G mode in graphene exhibits strong coupling to electrons, yet the comprehensive treatment of this interaction in the calculation of its temperature-dependent Raman spectrum remains incomplete. In this study, we calculate the temperature dependence of the G mode frequency and linewidth, and successfully explain the experimental trend, by accounting for the contributions arising from the first-order electron-phonon coupling, electron-mediated phonon-phonon coupling, and standard lattice anharmonicity. The generality of our approach enables its broad applicability to study phonon dynamics in materials where both electron-phonon coupling and anharmonicity are important.

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Nina Girotto Erhardt, Aloïs Castellano, J. P. Alvarinhas Batista, Raffaello Bianco, Ivor Lončarić, Matthieu J. Verstraete, Dino Novko. 2024-10-31. Electron-mediated anharmonicity and its role in the Raman spectrum of graphene. https://doi.org/10.1038/s41524-025-01610-9

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