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arXiv · 2501.00313

Two-dimensional moiré phonon polaritons

Hao Shi·Chu Li·Ding Pan·Xi Dai
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Abstract

Phonon polaritons (PhPs) are hybrid light-matter modes. We investigate them in two-dimensional (2D) materials with twisted moiré structures, revealing that the moiré potential creates a new class of `moiré PhPs'. These exhibit a fundamental spectral reconstruction into multiple branches and, crucially, electromagnetic wavefunctions that are nano-patterned by the superlattice. Through numerical simulations based on realistic lattice models, we confirm the existence of these intriguing modes. The inherent nanoscale structuring produces a robust, spatially varying near-field response, establishing moiré superlattices as a platform for engineering light-matter interactions.

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Hao Shi, Chu Li, Ding Pan, Xi Dai. 2025-09-09. Two-dimensional moiré phonon polaritons. https://doi.org/10.1021/acs.nanolett.5c03046

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