Wang Ju, Liu Wei, Wu Cuncun, Zhu Ning, Liu Congyue, Wang Shufeng
State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, Department of Physics, Peking University Beijing 100871 China
Collaborative Innovation Center of Extreme Optics, Shanxi University Taiyuan Shanxi 030006 China.
RSC Adv. 2020 Jan 15;10(5):2703-2708. doi: 10.1039/c9ra08619f. eCollection 2020 Jan 14.
Hybrid organic-inorganic lead halide perovskites have been investigated extensively within the last decades, for its great potential in efficient solar cells and as an ideal light source. Among the studies on stimulated emission (SE), the emission is either out-of-plane for polycrystalline films or in-plane with randomly aligned single microcrystals and nanowires. In this work, we revealed in-plane propagation of SE from bromine-based perovskite polycrystalline thin films (CHNHPbBr, or MAPbBr). The output from in-plane SE is an order higher than the out-of-plane emission. It is proposed that large crystalline flakes in the films lead to the in-plane lasing phenomena. The output coupling can be found at grain boundaries, intergrain gaps, and artificial structures. Simulative results support the experimental phenomenon that large crystalline grains are profitable for in-plane propagation and over 90% photons can be sufficiently outcoupled when the gap is larger than a micron. Considering the fabrication and handling convenience, we propose that the MAPbBr thin films can be easily integrated for in-plane applications as the light source for photonic chips
在过去几十年里，有机-无机杂化卤化铅钙钛矿因其在高效太阳能电池方面的巨大潜力以及作为理想光源而受到广泛研究。在关于受激发射（SE）的研究中，对于多晶薄膜，发射是面外的；对于随机排列的单个微晶和纳米线，发射是面内的。在这项工作中，我们揭示了基于溴的钙钛矿多晶薄膜（CHNHPbBr或MAPbBr）中SE的面内传播。面内SE的输出比面外发射高一个数量级。有人提出，薄膜中的大晶体薄片导致了面内激光现象。输出耦合可以在晶界、晶粒间隙和人工结构处找到。模拟结果支持了大晶粒有利于面内传播的实验现象，并且当间隙大于一微米时，超过90%的光子能够充分地向外耦合。考虑到制造和处理的便利性，我们提出MAPbBr薄膜可以很容易地集成用于面内应用，作为光子芯片的光源
