Generalized Bloch's Theorem for Cavity Exciton Polaron-Polaritons

Michael A. D. Taylor; Yu Zhang

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arXiv · 2601.03230

Generalized Bloch's Theorem for Cavity Exciton Polaron-Polaritons

Michael A. D. Taylor·Yu Zhang

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Abstract

We show that excitons coupled to cavity photons and phonons admit a generalized Bloch theorem when formulated for the conserved total crystal momentum. In minimal-coupling and Fr\"ohlich representations, the interchange of momenta between fermions and bosons breaks crystalline excitons' translational symmetry. In our symmetry-adapted frame, the Hamiltonian becomes block diagonal, without invoking approximations. The resulting formulation yields dispersions and optical responses of cavity exciton polaron-polaritons, enabling investigations that elucidate material properties in strong coupling.

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Michael A. D. Taylor, Yu Zhang. 2026-01-06. Generalized Bloch's Theorem for Cavity Exciton Polaron-Polaritons. https://arxiv.org/abs/2601.03230

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