红外与激光工程
2023, 52(4): 20220885
山东大学新一代半导体材料研究院, 山东大学晶体材料国家重点实验室, 济南
报道了脉冲半导体激光器侧面泵浦Nd:YAG同步声光调Q纳秒激光器。采用连续输出50 W的Nd:YAG侧面泵浦模块, 当半导体激光器泵浦脉宽250 μm、重复频率1 kHz、声光Q开关延时270 μm时, 实现了平均输出功率2.27 W、脉冲宽度71 ns的稳定调Q脉冲输出。
侧面泵浦 声光调Q 同步调制 side-pump acoustic-optic Q-switched synchronous modulation
山东大学新一代半导体材料研究院, 山东大学晶体材料国家重点实验室, 济南
脉冲半导体激光(LD)泵浦被动调Q微片激光器是产生小型化、大能量(mJ量级)、亚纳秒激光脉冲的主要技术途径。基于速率方程理论推导了脉冲LD泵浦被动调Q微片激光器首脉冲建立时间及多脉冲间隔时间方程, 数值求解并分析了泵浦功率、泵浦脉宽等参数对亚纳秒激光输出脉冲数目的影响规律, 在此基础上搭建了脉冲LD端面泵浦YAG/Nd:YAG/Cr4+:YAG微片激光器, 实现了单脉冲能量1.2 mJ、脉冲宽度574 ps、峰值功率2.1 MW, 光束质量因子M2=1.21的1 064 nm近衍射极限亚纳秒脉冲激光输出。
微片激光器 YAG/Nd:YAG/Cr4+:YAG晶体 被动调Q 速率方程 microchip laser YAG/Nd:YAG/Cr4+:YAG crystal passive Q-switching rate equation
深圳大学物理与光电工程学院 光电器件与系统重点实验室, 广东 深圳 518000
有机-无机卤化铅钙钛矿多晶薄膜太阳能电池在近几年的研究中实现了光电转换效率的快速增长。然而,其多晶结构的活性层导致器件仍然遭受到表面和晶界位置缺陷引起的性能衰减。本研究借助两种有机氢碘酸盐,即苯乙基碘化胺(Phenethylammonium iodide,PEAI)和邻氟苯乙胺碘(2-Fluorophenylethylammonium iodide,o-F-PEAI),在CH3NH3PbI3钙钛矿多晶薄膜表面形成钝化层。扫描电子显微镜和原子力显微镜分析结果显示,PEAI和o-F-PEAI处理后的钙钛矿薄膜晶界被钝化层明显填充,表面粗糙度也显著下降。另外,荧光寿命成像分析结果显示钝化后的钙钛矿薄膜具有更多的光子数和更长的荧光寿命。上述结果表明,PEAI和o-F-PEAI诱导的钝化层可以有效抑制多晶薄膜表面和晶界位置的缺陷复合行为。因此,钝化后的倒置结构钙钛矿太阳能电池器件功率转换效率(Power conversion efficiency,PCE)可以达到21%。此外,o-F-PEAI钝化处理后的器件由于氟离子的作用表现出更好的器件稳定性。
荧光寿命显微成像 倒置钙钛矿太阳能电池 表面钝化 fluorescence-lifetime imaging microscopy inverted perovskite solar cell surface passivation PEAI PEAI o-F-PEAI o-F-PEAI
钙钛矿材料优异的光电性能使钙钛矿太阳能电池成为目前发展速度最快的光伏技术之一。近期的研究发现无晶界的单晶钙钛矿薄膜拥有更低的缺陷密度、更高的载流子迁移率、更长的载流子复合寿命,并且还有较高的稳定性和更宽的光吸收范围,因此有望制备出更高效且更稳定的钙钛矿太阳能电池。本文简要介绍了单晶钙钛矿太阳电池的基本结构及其发展历程,着重介绍了有关单晶钙钛矿薄膜和块状单晶钙钛矿的制备方法,并且对不同方法制备的单晶钙钛矿太阳能电池的效率进行了比较,最后对单晶钙钛矿太阳能电池当前存在的问题以及未来发展进行了简要分析和展望。
单晶钙钛矿 钙钛矿太阳能电池 单晶钙钛矿薄膜 块状单晶钙钛矿 制备方法 single crystal perovskite perovskite solar cell single crystal perovskite film bulk single crystal perovskite preparation method
Author Affiliations
Abstract
Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, P. R. China
Inorganic quantum dots (QDs) have excellent optical properties, such as high fluorescence intensity, excellent photostability and tunable emission wavelength, etc., facilitating them to be used as labels and probes for bioimaging. In this study, CdSe@ZnS QDs are used as probes for Fluorescence lifetime imaging microscope (FLIM) and stimulated emission depletion (STED) nanoscopy imaging. The emission peak of CdSe@ZnS QDs centered at 526 nm with a narrow width of 19 nm and the photoluminescence quantum yield (PLQY) was 64%. The QDs presented excellent anti-photobleaching property which can be irradiated for 400 min by STED laser with 39.8mW. The lateral resolution of 42.0 nm is demonstrated for single QDs under STED laser (27.5mW) irradiation. Furthermore, the CdSe@ZnS QDs were for the first time used to successfully label the lysosomes of living HeLa cells and 81.5nm lateral resolution is obtained indicating the available super-resolution applications in living cells for inorganic QD probes. Meanwhile, Eca-109 cells labeled with the CdSe@ZnS QDs was observed with FLIM, and their fluorescence lifetime was around 3.1 ns, consistent with the in vitro value, suggesting that the QDs could act as a satisfactory probe in further FLIM-STED experiments.
CdSe@ZnS QDs FLIM STED living cells Journal of Innovative Optical Health Sciences
2019, 12(5): 1940003