Deciphering the Ultrafast Nonlinear Optical Properties and Dynamics of Pristine and Ni-Doped CsPbBr 3 Colloidal 2D Nanocrystals

• Published in: The journal of physical chemistry letters 2019-08
• Main Authors: Ketavath, Ravi, Katturi, Naga Krishnakanth, Ghugal, Sachin G, Kolli, Hema Kumari, Thokala, Swetha, Soma, Venugopal Rao, Murali, Banavoth
• Format: Article
• Language: English
• ISSN: 1948-7185
• DOI: 10.1021/acs.jpclett.9b02244

While the unabated race persists in accomplishing the record efficiencies in solar cells and other photonic/optoelectronic devices using the lead halide perovskite absorbers, a comprehensive picture of the correlated third-order nonlinear optical (NLO) properties is yet to be established. The present study is aimed at deciphering the role of dopants on multi-photon absorption (MPA) properties of intentionally engineered CsPbBr3 colloidal nanocrystals (NCs). The charge separation of the plasmon-semiconductor conduction band owing to the hot electron transfer at the interface was demystified using the dynamics of the bleached spectral data from femtosecond (fs) transient absorption spectroscopy with broadband capabilities. The NLO properties studied through fs Z-scan technique revealed that nickel doped CsPbBr3 nanocrystals exhibited strong third-order NLO susceptibility of ~10-10 esu. The exotic photophysical phenomena in these pristine and Ni-doped CsPbBr3 colloidal 2D NCs reported herein are believed to provide the avenues to address the critical variables involved in the structural differences and their correlated optoelectronic properties.