Non-Markovian dynamics in guanidinium-based perovskites.

Markovian and non-Markovian measurements play a critical role in characterizing open quantum systems and elucidating phenomena associated with radiation absorption processes. Motivated by recent advances in solar radiation harvesting technologies, this work presents a theoretical and computational study of guanidinium-based perovskites with [Formula: see text] substitution. Using ab initio-inspired modeling and open quantum system simulations, we examine the non-Markovian dynamics governing UV-Vis light-matter interactions in these materials. Our simulations reveal that electronic states at the surface of guanidinium perovskites suppress Pb-I hybridization and enhance the dielectric response, resulting in improved polarization and longer charge carrier lifetimes. Non-Markovian analyses further show that guanidinium cations promote low-energy vibrational modes and facilitate the formation of large polarons. Finally, we demonstrate that tuning spectroscopic parameters critically affects the manifestation of Markovian and non-Markovian features across a wide temperature range in these perovskite structures.