Exploring Exciton and Polaron Dominated Photo-physical Phenomena in Ruddlesden-Popper Phases of Ban+1ZrnS3n+1 (n=[1-3]) from Many Body Perturbation Theory
arXiv:2105.03757 · doi:10.1021/acs.jpclett.1c01486
Abstract
Ruddlesden-Popper (RP) phases of BaZrS (n=[1-3]) are evolved as new promising class of chalcogenide perovskites in the field of optoelectronics, especially in solar cells. However, detailed studies regarding its optical, excitonic, polaronic and transport properties are hitherto unknown. Here, we have explored the excitonic and polaronic effect in RP phases of BaZrS (n=[1-3]) using several first-principles based state-of-the-art methodologies under the framework of Many Body Perturbation Theory. Unlike it's bulk counterpart, the optical and excitonic anisotropy are observed in BaZrS (n=[1-3]) RP phases. From Wannier-Mott approach, we show that in the RP phases of this class of chalcogenide perovskites, capturing the ionic contribution to the dielectric constant is important. We report significant ionic contribution and relatively smaller electron-phonon coupling constant for BaZrS in comparison to the bulk BaZrS. The exciton binding energy is found to be dependent on the presence of large electron-phonon coupling. The charge carrier mobility is maximum in BaZrS, computed employing deformation potential of the same. As per our analysis, the optical phonon modes are observed to dominate the acoustic phonon modes, leading to decrease in polaron mobility on increasing n in BaZrS (n=[1-3]).
References in corpus (5)
- Optical Phonons in Methylammonium Lead Halide Perovskites and Implications for Charge Transport
- Chalcogenide Perovskites- an Emerging Class of Ionic Semiconductors
- Efficient approach to solve the Bethe-Salpeter equation for excitonic bound states
- Ti-alloying of BaZrS3 chalcogenide perovskite for photovoltaics
- Optoelectronic Properties of Chalcogenide Perovskites by Many-Body Perturbation Theory