Understanding thickness-dependent electronic and optical transitions of Ruddlesden-Popper halide perovskites

Ruddlesden-Popper halide perovskites are layered heterostructures that are promising candidates for effective optoelectronic devices due to their photoefficiency and stability. Despite their high tunability through substitution and stoichiometry, the physics that control the resulting electronic and optical properties are still not fully understood. We investigate the dependence of the band gap and exciton binding energy on the inorganic layer thickness through the tight binding approximation and nonlocal screened Coulomb potential, making use of material properties of three-dimensional perovskites. Our theory provides an analysis of the optical gap measured by absorption and photoluminescence.