Tang Yuxiang, Zhang Yanbin, Cao Fan, Sui Yizhen, Cheng Xiang'ai, Shi Lei, Jiang Tian
Opt Lett. 2022 Aug 1;47(15):3916-3919. doi: 10.1364/OL.461926.
Integrating metal halide perovskites onto plasmonic nanostructures has recently become a trending method of enabling superior emissive performance of perovskite nanophotonic devices. In this work, we present an in-depth study on the spontaneous emission properties of hybrid systems comprising CsPbBr nanocrystals and silver nanostructures. Specifically, a 5.7-fold increment of the photoluminescence (PL) intensity and a 1.65-fold enhancement of the PL relaxation rate is attained when the transition energy of CsPbBr is spectrally resonant with the oscillational frequency of Ag nanodisks (NDs), which is attributed to the intense exciton-plasmon coupling-induced Purcell effect. Furthermore, a 540-fs ultrafast energy transfer from the CsPbBr excitons to Ag plasmons is revealed by femtosecond pump-probe experiments, suggesting the key mechanism responsible for the Purcell-enhanced radiative emission. Our finding offers a unique understanding of the enhanced emissive behavior in the plasmon-coupled perovskite system and paves the way for further applications.
将金属卤化物钙钛矿与等离子体纳米结构相结合，最近已成为一种使钙钛矿纳米光子器件实现卓越发光性能的热门方法。在这项工作中，我们对由CsPbBr纳米晶体和银纳米结构组成的混合系统的自发发射特性进行了深入研究。具体而言，当CsPbBr的跃迁能量与Ag纳米盘（NDs）的振荡频率在光谱上共振时，光致发光（PL）强度增加了5.7倍，PL弛豫速率提高了1.65倍，这归因于强烈的激子 - 等离子体耦合诱导的珀塞尔效应。此外，飞秒泵浦 - 探测实验揭示了从CsPbBr激子到Ag等离子体的540飞秒超快能量转移，这表明了珀塞尔增强辐射发射的关键机制。我们的发现为等离子体耦合钙钛矿系统中增强的发光行为提供了独特的理解，并为进一步的应用铺平了道路。
