Correlation between Dielectric Constants and Exciton Binding Energies in 2D Metal Halide Perovskites

2D metal halide perovskites (HPs) is a class of materials that have recently gained traction in the material science community due to the tunability of their band gap (E_g) and exciton binding energies (E_b). Understanding what affects these parameters is crucial in progressing perovskites to be utilized in photovoltaics, light-emitting diodes, and optoelectronics. Our research seeks to better understand the material properties, such as the dielectric constant, of HPs that affect the exciton binding energy. Utilizing interdigitated electrodes (IDE) and impedance spectroscopy we can probe the dielectric response at varying frequencies of HPs and other thin films. Our research shows a correlation in HPs between the dielectric constant and the exciton binding energy. This research contributes to the ever-growing understanding of HPs and how to tune them to desired applications.