碳纳米管/二硒化钼有机玻璃的非线性吸收、非线性散射和光限幅特性  

Nonlinear absorption, nonlinear scattering, and optical limiting properties of carbon nanotube/molybdenum diselenide organic glass

作　　者：孙悦 曲斌[3] 全保刚 Sun Yue;Qu Bin;Quan Bao-Gang(College of Science,Harbin Engineering University,Harbin 150001,China;Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences Beijing 100190,China;College of Science,Northeast Agricultural University,Harbin 150030,China)

机构地区：[1]哈尔滨工程大学理学院,哈尔滨150001 [2]中国科学院物理研究所,北京凝聚态物理国家研究中心,北京100190 [3]东北农业大学理学院,哈尔滨150030

出　　处：《物理学报》2018年第23期182-189,共8页Acta Physica Sinica

摘　　要：MoSe_2的禁带宽度较窄(1.1—1.5 eV),且具有可调谐的激子光电效应,这样使其在光致发光、光电晶体管、太阳能电池和光学非线性等方面具有潜在的应用价值.然而,纯的MoSe_2的光生电子空穴复合率较高,限制了其在某些光学领域中的应用.通过设计MoSe_2的复合材料,可以降低材料的光生电子空穴复合率,从而扩展其应用领域.首先,通过热溶剂法合成CNT/MoSe_2复合材料;然后,通过浇铸法将其分散在甲基丙烯酸甲酯(MMA)中制备成有机玻璃,其中MMA会聚合成聚甲基丙烯酸甲酯(PMMA),并利用改进的Z-扫描技术首次对CNT/MoSe_2/PMMA有机玻璃的非线性吸收、非线性散射和光限幅特性进行了研究.研究表明,随着输入能量的变化,通过调节输入能量, CNT/MoSe_2/PMMA有机玻璃表现出饱和吸收(SA)和从SA到反饱和吸收的转变.结合材料特性及应用条件要求,可以得到CNT/MoSe_2/PMMA有机玻璃在光学设备,如光学限制器和锁模/调Q激光器等方向具有较好的应用前景.Because MoSe2 has broadband saturable absorption, and higher nonlinear refractive index. Compared with MoS2,thin-layered MoSe2 possesses very attractive properties, including narrow bandgap, low optical absorption coefficient, and large spin-splitting energy at the top of the valence band. The narrow bandgap and low optical absorption coefficient could make MoSe2 more applicable than MoS2. And the tunable excitation photoelectric effecthas great potential applications in the fields of photoluminescence, phototransistor, solar cells, nonlinear optics and other aspects. However,pure MoSe2 has high photogenerated recombination rate, thus limiting its applications in some optical fields. By designing nanocomposites of MoSe2, the photogenerated recombination rate of these materials can be reduced and their application field can be broadened. In this work, MoSe2 nanocomposites are prepared by simple methods. The twodimensional layered MoSe2 nanosheets are combined with nanorods. By integrating the surface effect, small size effect and interfacial effect of CNT, the optical nonlinearity and optical limiting performance of MoSe2 composites are improved.The CNT/MoSe2 composite nanomaterials are first synthesized based on narrower band gap and lower light absorption coefficient of MoS2 than those of MoSe2 by growing MoSe2 nanoparticles on the surface of CNT through a solvothermal method, and then is dispersed in methyl methacrylate(MMA) to prepare an organic glass by a casting method, and the MMA is polymerized into poly(methyl methacrylate)(PMMA). The nonlinear absorption(NLA), nonlinear scattering(NLS) and optical limiting(OL) properties of the CNT/MoSe2/PMMA organic glass are studied by the modified Zscan technique for the first time. The CNT/MoSe2/PMMA organic glass exhibits the saturable absorption(SA) and a changeover from SA to reverse saturable absorption by adjusting input energy. The experimental results show that the CNT/MoSe2/PMMA plexiglass exhibits better anti-saturation absorption and higher optical limiting

关 键 词：MoSe2纳米片 复合纳米材料 光学非线性 

分 类 号：O437[机械工程—光学工程]