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1. Theory of Exciton-phonon Coupling

   https://doi.org/10.1103/PhysRevB.105.085111  

   Antonios, G.; Louie, S. G. (January 2022, Physical Review)
2. Exciton dispersion and exciton–phonon interaction in solids by time-dependent density functional theory

   https://doi.org/10.1063/5.0137326  

   Liu, Junyi; Lu, Gang; Zhang, Xu (January 2023, The Journal of Chemical Physics)

   Understanding, predicting, and ultimately controlling exciton band structure and exciton dynamics are central to diverse chemical and materials problems. Here, we have developed a first-principles method to determine exciton dispersion and exciton–phonon interaction in semiconducting and insulating solids based on time-dependent density functional theory. The first-principles method is formulated in planewave bases and pseudopotentials and can be used to compute exciton band structures, exciton charge density, ionic forces, the non-adiabatic coupling matrix between excitonic states, and the exciton–phonon coupling matrix. Based on the spinor formulation, the method enables self-consistent noncollinear calculations to capture spin-orbital coupling. Hybrid exchange-correlation functionals are incorporated to deal with long-range electron–hole interactions in solids. A sub-Hilbert space approximation is introduced to reduce the computational cost without loss of accuracy. For validations, we have applied the method to compute the exciton band structure and exciton–phonon coupling strength in transition metal dichalcogenide monolayers; both agree very well with the previous GW-Bethe–Salpeter equation and experimental results. This development paves the way for accurate determinations of exciton dynamics in a wide range of solid-state materials. 

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3. Exciton-Phonon Interaction and Relaxation Times from First Principles

   https://doi.org/10.1103/PhysRevLett.125.107401  

   Chen, Hsiao-Yi; Sangalli, Davide; Bernardi, Marco (August 2020, Physical Review Letters)
4. Exciton–phonon interactions in nanocavity-integrated monolayer transition metal dichalcogenides

   https://doi.org/10.1038/s41699-020-0156-9  

   Rosser, David; Fryett, Taylor; Ryou, Albert; Saxena, Abhi; Majumdar, Arka (December 2020, npj 2D Materials and Applications)

   null (Ed.)
5. PRB Exciton-activated effective phonon magnetic moment in monolayer MoS2

   https://doi.org/10.5281/zenodo.11493104  

   He, Rui (June 2024, Zenodo)

   Optical excitation of chiral phonons plays a vital role in studying the phonon-driven magnetic phenomena in solids. Transition metal dichalcogenides host chiral phonons at high symmetry points of the Brillouin zone, providing an ideal platform to explore the interplay between chiral phonons and valley degree of freedom. Here, we investigate the helicity-resolved magneto-Raman response of monolayer MoS2 and identify a doubly degenerate Brillouin-zone-center chiral phonon mode at ∼270cm−1. Our wavelength- and temperature-dependent measurements show that this chiral phonon is activated through the resonant excitation of 𝐴 exciton. Under an out-of-plane magnetic field, the chiral phonon exhibits giant Zeeman splitting, which corresponds to an effective magnetic moment of ∼2.5⁢𝜇𝐵. Moreover, we carry out theoretical calculations based on the morphic effects in nonmagnetic crystals, which reproduce the linear Zeeman splitting and Raman cross section of the chiral phonon. Our study provides important insights into lifting the chiral phonon degeneracy in an achiral covalent material, paving a route to excite and control chiral phonons. 

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