Ultrafast exciton-polaron dynamics in moiré superlattices.

We develop a fully computational framework to simulate exciton-polaron-polariton formation in moiré superlattices under strong light-matter coupling. The model combines parametrized moiré potentials with analytical cavity representations and non-Hermitian quantum propagation to capture hybridization between moiré-confined excitons and cavity photons. The present model uses a reduced first-harmonic parametrization of the moiré potential and omits atomic-scale reconstruction and material-specific microscopic details. Even so, it captures the leading energy modulation and provides qualitative polariton dynamics predictions relevant to current experiments. The calculated detuning-coupling map reveals the onset of strong coupling near ≈ 0.035 eV, yielding a transient Rabi splitting of ≈ 6 meV that collapses within 0.3 ps due to carrier-induced dephasing. Time-resolved spectra show ultrafast conversion from neutral excitons to exciton-polarons with formation and depletion times of ≈ 0.24 ps and ≈ 0.27 ps, respectively. Principal component and Bayesian analyses quantitatively recover the optimal coupling ( ≈ 0.034 eV) and cavity resonance ( ≈ 1.72 eV), consistent with reported Rabi splittings in twisted TMD nanocavity systems. This work provides a predictive computational platform for understanding correlated exciton-photon phenomena in two-dimensional moiré quantum materials.