Multiscale Dynamics from Picoseconds to Milliseconds: Bridging Spin Coherence and Metastable Photocharging in CsPbX<sub>3</sub> Perovskite Quantum Dots.

Cheng, Lin; Hu, Rongrong; Li, Xiaoyang; Men, Yumeng; Liang, Pan; Li, Jinlei; Jia, Tianqing; Sun, Zhenrong et al. · Nano Lett · 2025

basic_science · Level V

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Abstract

All-inorganic lead halide perovskite quantum dots (PQDs) have attracted significant attention due to their exceptional optoelectronic properties and unique spin-related behaviors. This study investigates the interplay between hole spin coherence and photocharging processes in solution-processed CsPbCl<sub>3</sub> PQDs by using time-resolved Faraday rotation spectroscopy. Our research reveals a room-temperature hole spin dephasing time of ∼60 ps and a hole <i>g</i> factor of ∼1.73. Photocharging dynamics are probed via a spin detection technique based on a prepump-pump-probe methodology, uncovering biphasic formation kinetics with time constants of 54 and 327 ps and three lifetimes of 62 μs, 335 μs, and >1 ms for the photocharged states. These multiscale dynamics are similarly observed in CsPbBr<sub>3</sub> PQDs. This study provides a quantitative framework linking spin coherence to photocharging processes, deepening the understanding of spin-charge correlations in lead halide perovskites, and offering practical guidelines for optimizing quantum coherence in solution-processed nanomaterials.