一种近红外光记录与存储材料——克酮酸染料的三阶非线性光学性质

Third-Order Nonlinear Optical Properties of Croconium Dye for a Kind of Near Infrared Dye Used as Optical Record and Storage Material

克酮酸染料是一类新型的近红外吸收染料,由于具有良好的光热稳定性和荧光性能,因而在光记录与存储等领域有着潜在的应用价值.本文利用简并四波混频技术,在近红外区不同吸收波长,在脉宽为130 fs条件下研究了一种吲哚克酮酸染料在溶液和薄膜中的三阶非线性光学性质.该克酮酸染料在773 nm,四氢呋喃溶液中的共振三阶超分子极化率γ为5.3×10-29esu,在薄膜中的共振三阶非线性极化率χ(3)值达到10-8esu数量级.同时,对于三阶非线性光学响应及其动力学机制也进行了研究和探讨.

As a new type of near infrared dye, croconium dyes have drawn much attention for their potential applications in the fields of optical record and storage, and nonlinear optical materials because of their thermal and optical stability as well as intense fluorescence. The third-order optical nonlinearities and responses of a croconium dye （ 1,3-bis [ （3,3-dimethylindolin-2-ylidene） methyl ] croconine） in tetrahydrofuran （THF） solution and in poly（methyl methacrylate） （PMMA） coating films were measured using a femtosecond degenerate four-wave mixing （DFWM） technique with a laser pulse of 130 fs system under resonant conditions. The molecular hyperpolarizability, γ of the croconium dye in THF solution was determined to be about 5.3 × 10^- 29 esu, and the third-order nonlinear optical susceptibilities, X^（3） of the dye was measured to be of the order of 10 present PMMA coating films containing the croconium 8 esu. Furthermore, the dynamic of DFWM optical response for croconium dye was also studied and analysed.