Extending tight-binding models from bulk to layered halide perovskites
Résumé
In recent years, metal halide perovskites have become the focus of intense research due to their excellent and tunable optoelectronics, with potential applications for single-junction and tandem photovoltaics, efficient light emission, spintronics, single-photon emission and entangled photon pair generation. To fully realize the technological promises of this class of materials, the coupling between free carriers or excitons and lattice vibrations and its impact on the optoelectronic properties remain to be understood. Achieving this requires a sustained theoretical effort involving mutiple approaches from ab initio calculations to effective mass methods. Within this range, tight-binding models are flexible enough to incorporate disorder and complex heterostructures, but are still based on a microscopic atomic picture and are thus relevant for explicit descriptions of carrier-lattice interactions and structure-property relationships. In this talk, I will present a symmetry-based semi-empirical tight-binding model bulk halide perovskites in the cubic phase [1-3], and discuss its extension to other perovskite structures such as layered compounds. This generalization will lead to a deeper understanding of the relationships between structure, composition and optoelectronic properties in bulk, layered and nanocrystalline perovskites.