on above bandgap excitations, excitons populate and diffuse toward the boundary, where the potential gradient blocks excitons and the edge states are formed through interband transitions within 400 fs. With below bandgap excitations, edge states are slowed down to 1.1 ps due to the weakened valence orbital coupling. These results shed light on the fundamental exciton dissociation processes on the boundary of functionalized TMDCs, enabling the ground work for applications in optoelectronics and light-harvesting.22:T43b,Out-of-plane (OP) exciton-based emitters in two-dimensional semiconductor materials are attractive candidates for novel photonic applications, such as radially polarized sources, integrated photonic chips, and quantum communications. However, their low quantum efficiency resulting from forbidden transitions limits their practicality. In this work, we achieve a giant enhancement of up to 34000 for OP exciton emission in indium selenide (InSe) via a designed Ag nanocube-over-Au film plasmonic nanocavity. The large photoluminescence enhancement factor (PLEF) is attributed to the induced OP local electric field (E_z) within the nanocavity, which facilitates effective OP exciton-plasmon interaction and subsequent tremendous enhancement. Moreover, the nanoantenna effect resulting from the effective interaction improves the directivity of spontaneous radiation. Our results not only reveal an effective photoluminescence enhancement approach for OP excitons but also present an avenue for designing on-chip photonic devices with an OP dipole orientation.23:T4d4,Low-dimensional lead halides have attracted increasing attention due to their potential application as single-component white-light emitters. These materials exhibit a complex emission spectral structure, ranging from free exciton narrowband emissions to self-trapped exciton broadband emissions. However, there is still no consensus for the underlying physical mechanism, especially in the spectrum with both narrowband and broadband emissions. Here we aim to elucidate the correlation between the emission spectrum and the exciton-phonon coupling in the mixed halide perovskite BA₂Pb(Br_xCl_1-x)₄. Our findings reveal that the interplay between exciton localization and delocalization results in an intermediate exciton-phonon coupling, leading to line shapes beyond the Huang-Rhys model for the self-trapped exciton. By incorporating the exciton motional effect, we establish a unified photophysical model describing the emission spectrum from the self-trapped exciton type to the free exciton type. These results provide essential insights into the mechanisms governing exciton-phonon interactions and offer ways to control white-light emission in two-dimensional perovskites.

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