Liu Wei, Li Yaolong, Yu Haoran, Wang Ju, Hu Aiqin, Jia Shangtong, Li Xiaofang, Yang Hong, Dai Lun, Lu Guowei, Liu Yunquan, Wang Shufeng, Gong Qihuang
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.
Adv Mater. 2021 Jun;33(25):e2100775. doi: 10.1002/adma.202100775. Epub 2021 May 13.
Perovskite microcavities have excellent photophysical properties for integrated optoelectronic devices, such as nanolasers. Imaging and controlling the photonic modes within the cavity are fundamentally important to understand and develop applications. Here, photoemission electron microscopy (PEEM) is used to image the photonic modes within optical microcavities with a nanometer-scale spatial resolution. From a CsPbBr microcavity, hybrid mode patterns are observed. Spatial frequency spectrum analysis on the patterns uncovers the characteristic cavity modes, which are modeled with transverse magnetic (TM) and transverse electric (TE) waves, and assigned to exciton-polariton modes. Based on this understanding, the light focus in a designed microcavity is imaged in real space and controlled by the light field polarization. The study confirms that the cavity modes in perovskites can be effectively observed by the PEEM technique under resonant excitation, which, in turn, promotes the design of optoelectronic devices based on perovskite microcavities.
钙钛矿微腔对于集成光电器件（如纳米激光器）具有优异的光物理性质。对腔内光子模式进行成像和控制对于理解和开发应用至关重要。在此，光发射电子显微镜（PEEM）被用于以纳米级空间分辨率对光学微腔内的光子模式进行成像。从一个CsPbBr微腔中，观察到了混合模式图案。对这些图案进行空间频谱分析揭示了特征腔模式，这些模式用横向磁（TM）波和横向电（TE）波进行建模，并被归为激子 - 极化激元模式。基于这一认识，在设计的微腔中的光聚焦在实空间中成像，并由光场极化控制。该研究证实，在共振激发下，通过PEEM技术可以有效地观察到钙钛矿中的腔模式，这反过来又促进了基于钙钛矿微腔的光电器件的设计。
