Nonlinear Absorption and Low-threshold Two-photon Pumped Amplified Stimulated Emission from FAPbBr_(3) Nanocrystals  

基于FAPbBr_(3)钙钛矿纳米晶体的非线性吸收和低阈值双光子泵浦放大自发辐射

作　　者：WANG Yajuan TAY Yong Kang Eugene WANG Fang YU Sheng SUM Tze Chien LIU Wei 王亚娟;TAY Yong Kang Eugene;王芳;余盛;岑子健;刘威(宁波工程学院材料与化学工程学院,浙江宁波315211;南洋理工大学物理与数学科学学院,新加坡637371;浙江农林大学光机电工程学院,浙江杭州311300)

机构地区：[1]School of Materials and Chemical Engineering,Ningbo University of Technology,Ningbo 315211,China [2]School of Physical and Mathematical Sciences,Nanyang Technological University,Singapore 637371,Singapore [3]College of Optical,Mechanical and Electrical Engineering,Zhejiang A&F University,Hangzhou 311300,China

出　　处：《发光学报》2024年第8期1281-1291,共11页Chinese Journal of Luminescence

摘　　要：Formamidinium lead bromide(FAPbBr_(3))nanocrystals(NCs)have been considered to be a good optoelectronic material due to their pure green emission,excellent stability and superior carrier transport characteristics.However,two-photon pumped amplified spontaneous emission(ASE)and the corresponding nonlinear optical properties of FAPbBr_(3) NCs are scarcely revealed.Herein,we synthesized colloidal FAPbBr_(3) NCs with different sizes by changing the molar ratio of FABr/PbBr_(2) in the precursor solution,using ligand assisted precipitation(LARP)technology at room temperature.Photoluminescence(PL)and time resolved photoluminescence(TRPL)spectroscopy were measured to characterize their ASE properties.And their nonlinear optical properties were studied through the Zscan technique and the two-photon excited fluorescence method.The stimulated emission properties including oneand two-photon pumped ASE have been realized from FAPbBr_(3) NCs.With large two-photon absorption coefficient(0.27 cm/GW)and high non-linear absorption cross-section(7.52×10^(5) GM),ASE with threshold as low as 9.8μJ/cm^(2) and 487μJ/cm^(2) have been obtained from colloidal FAPbBr_(3) NCs using one-and two-photon excitations.These results indicate that as a new possible green-emitting frequency-upconversion material with low thresholds,FAPbBr_(3) NCs hold great potential in the development of high-performance two-photon pump lasers.甲脒铅溴(FAPbBr_(3))钙钛矿纳米晶因其更标准的绿光发射、优异的稳定性和载流子传输特性而被认为是一种良好的光电材料。然而,FAPbBr_(3)纳米晶体的双光子泵浦放大自发辐射(ASE)和相应的非线性光学特性却很少被报道。本文在室温下通过改变前驱体溶液中FABr/PbBr_(2)的摩尔配比,利用配体辅助沉淀(LARP)技术合成了不同尺寸的胶体FAPbBr_(3)纳米晶体。测量了光致发光(PL)和时间分辨光致发光光谱(TRPL),以表征其ASE特性。并利用Z扫描技术和双光子激发荧光方法研究了它们的非线性光学特性。实现了FAPbBr_(3)纳米晶的单光子和双光子泵浦放大自发辐射,阈值分别低至9.8μJ/cm^(2)和487μJ/cm^(2),具有大的双光子吸收系数(0.27 cm/GW)和高的非线性吸收截面(7.52×10^(5) GM)。这些结果表明,作为一种新的有前景的低阈值绿光发射频率上转换材料,FAPbBr_(3)纳米晶在开发高性能双光子泵浦激光器方面具有巨大的潜力。

关 键 词：perovskites formamidinium lead bromide nanocrystals NONLINEAR optical gain amplified spontaneous emission 

分 类 号：O482.31[理学—固体物理]