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arXiv · 2403.09692

Phonon Linewidths in Twisted Bilayer Graphene near Magic Angle

Shinjan Mandal·Indrajit Maity·H. R. Krishnamurthy·Manish Jain
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Abstract

We present a computational study of the phonon linewidths in twisted bilayer graphene arising from electron-phonon interactions and anharmonic effects. The electronic structure is calculated using distance-dependent transfer integrals based on the atomistic Slater-Koster tight-binding formalism, including electron-electron interactions treated at the Hartree level, and the phonons are calculated using classical force fields. These ingredients are used to calculate the phonon linewidths arising from electron-phonon interactions. Furthermore, anharmonic effects on the linewidths are computed using the mode-projected velocity autocorrelation function obtained from classical molecular dynamics. We predict a moiré potential induced splitting of this mode, which arises due to contributions from high symmetry stacking regions. Our findings show that both electron-phonon and anharmonic effects have a significant impact on the linewidth of the Raman active G mode near the magic angle.

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Shinjan Mandal, Indrajit Maity, H. R. Krishnamurthy, Manish Jain. 2024-07-02. Phonon Linewidths in Twisted Bilayer Graphene near Magic Angle. https://doi.org/10.1103/physrevb.110.125421

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