Excitonics in 2D Perovskites

This chapter provides an overview of two-dimensional organic-inorganic hybrid perovskites (2D-OIHP) excitonic properties. It discusses their optical transitions, quasi-particle interactions, and their emerging applications in the recent years. The exciton binding energies of these 2D-OIHPs are in the order of hundreds of meV. The large exciton binding energy gives rise to pronounced room temperature excitonic effects. Broadband visible emission is an interesting and technologically important optical phenomenon that was reported in several 2D-OIHPs. Defect-related broadband emission could also be another origin for white light emission (WLE) in 2D perovskites. The large exciton oscillator strength and binding energy in 2D-OIHPs also give rise to strong exciton-photon coupling. One of the simplest theoretical models to describe the exciton-photon coupling phenomenon is the Jaynes-Cummings model. Quantum and dielectric confinement effect in 2D-OIHPs strongly enhanced its excitonic binding energy and oscillator strength, hence endowing it with great potential for exciton-based applications.