MoS_2溶液的波长选择性光限幅效应研究

采用N,N-二甲基甲酰胺(DMF)和四氢呋喃(THF)为溶剂,用离散法制备二硫化钼(MoS2)悬浮溶液,并用开孔Z扫描方法研究其在可见和近红外区域的非线性光学特性.结果显示,在强激光照射下,MoS2(in THF)悬浮溶液在可见波段(530 nm)透过率增强为常光透过率的1.54倍,表现为饱和吸收;在近红外波段(790 nm)透过率减弱为常光透过率的0.6倍,表现为反饱和吸收,具有很好的波长选择性光限幅效应.而作为对比的MoS2(in DMF)悬浮溶液在全波段透过率降低,呈现反饱和吸收特性,波长选择性不明显.机理解释可能为饱和吸收和热效应导致的自衍射两种机制联合作用.

Wavelength selective optical limiting effect on MoS2 solution

Using discrete method, N,N-Dimethylformamide (DMF) and tetrahydrofuran(THF) are adopted as solvent to fabricate MoS₂ suspension solution, and its nonlinear optical properties in the visible and near infrared region are studied by open aperture Z-scan method. The results show that under the intense laser, in MoS₂ (in DMF) suspension solution, saturable absorption property can be detected in the visible waveband (530 nm), showing that its transmittance is 1.54 times of ordinary, and reverse saturable absorption can be observed in the near infrared region (790 nm), indicating that its transmittance is 0.6 time of ordinary one and very good wavelength selection optical limiting effect. As a comparison, in the MoS₂ (in DMF) suspension solution there does not appear the wavelength selection feature, but the reverse saturable absorption is present in all band. This phenomena may be produced through the two mechanisms: saturableabsorption and thermally-induced self-diffraction.
Keywords： molybdenum disulfide wavelength selection saturable absorption optical limiting