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arXiv · 2502.13814

Inherited Berry curvature of phonons in Dirac materials with time-reversal symmetry

Sayandip Ghosh·Selçuk Parlak·Ion Garate
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Abstract

The Berry curvature of phonons is an active subject of research in condensed matter physics. Here, we present a model in which phonons acquire a Berry curvature through their coupling to electrons in crystals with time-reversal symmetry. We illustrate this effect for BaMnSb$_2$, a quasi two-dimensional Dirac insulator, whose low-energy massive Dirac fermions generate a phonon Berry curvature that is proportional to the electronic valley Chern number.

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Sayandip Ghosh, Selçuk Parlak, Ion Garate. 2025-02-19. Inherited Berry curvature of phonons in Dirac materials with time-reversal symmetry. https://doi.org/10.1103/7f8x-fkx9

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