Manipulation of hot carrier cooling dynamics in two-dimensional Dion–Jacobson hybrid perovskites via Rashba band splitting

• Published in: Nature communications Vol. 12; no. 1; pp. 3995 - 9
• Main Authors: Yin, Jun, Naphade, Rounak, Maity, Partha, Gutiérrez-Arzaluz, Luis, Almalawi, Dhaifallah, Roqan, Iman S., Brédas, Jean-Luc, Bakr, Osman M., Mohammed, Omar F.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 28.06.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 119/118; 140/125; 140/133; 147/3; 639/301/1034/1035; 639/301/357/1018; 639/301/357/995; 639/624/1107/527; Absorption spectroscopy; Augers; Cooling; Electron spin; First principles; Hot electrons; Humanities and Social Sciences; multidisciplinary; Optoelectronic devices; Perovskites; Phonons; Scattering; Science; Science (multidisciplinary); Splitting
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-24258-7

Hot-carrier cooling processes of perovskite materials are typically described by a single parabolic band model that includes the effects of carrier-phonon scattering, hot phonon bottleneck, and Auger heating. However, little is known (if anything) about the cooling processes in which the spin-degenerate parabolic band splits into two spin-polarized bands, i.e., the Rashba band splitting effect. Here, we investigated the hot-carrier cooling processes for two slightly different compositions of two-dimensional Dion–Jacobson hybrid perovskites, namely, (3AMP)PbI 4 and (4AMP)PbI 4 (3AMP = 3-(aminomethyl)piperidinium; 4AMP = 4-(aminomethyl)piperidinium), using a combination of ultrafast transient absorption spectroscopy and first-principles calculations. In (4AMP)PbI 4 , upon Rashba band splitting, the spin-dependent scattering of hot electrons is responsible for accelerating hot-carrier cooling at longer delays. Importantly, the hot-carrier cooling of (4AMP)PbI 4 can be extended by manipulating the spin state of the hot carriers. Our findings suggest a new approach for prolonging hot-carrier cooling in hybrid perovskites, which is conducive to further improving the performance of hot-carrier-based optoelectronic and spintronic devices. Hybrid perovskite is a promising class of material for optoelectronic applications due to the slow hot-carrier cooling, yet the process is not well-understood in material with Rashba band splitting. Here, the authors reveal spin-flipping and spin-dependent scattering of hot electrons are responsible for accelerating the cooling at longer delays.