Large electronic third-order optical nonlinearities of cyanine dyes measured by resonant femtosecond degenerate four-wave mixing
Large electronic third-order optical nonlinearities of cyanine dyes measured by resonant femtosecond degenerate four-wave mixing
复制标题
DOI：
10.1016/s0925-3467(02)00120-9
复制
发表时间：
2003
影响因子：
3.9
通讯作者：
K. Kasatani
中科院分区：
文献类型：
--
作者：
K. Kasatani
利用飞秒简并四波混频（DFWM）技术测量了几种菁染料在共振条件下的三阶光学非线性。的DFWM信号的时间分布测量的时间分辨率为0.3 ps，并被发现包括至少两个组件，相干的瞬时非线性响应和延迟响应与几百皮秒的衰减时间常数。后者可以归因于这些染料的分子旋转弛豫。在1×10−5moldm−3的极低浓度下，这些染料的非线性光学极化率的电子分量χe xxxx（3）的值为1.2 ×10−12esu。分子超极化率的电子分量γe计算为每种染料的1×10−28esu。
Third-order optical nonlinearities of several cyanine dyes were measured under resonant conditions by the femtosecond degenerate four-wave mixing (DFWM) technique. Temporal profiles of the DFWM signal were measured with a time resolution of 0.3 ps, and were found to consist of at least two components, the coherent instantaneous nonlinear response and the delayed response with a decay time constant of several hundred picoseconds. The latter can be attributed to molecular rotational relaxation of these dyes. The values of electronic component of the optical nonlinear susceptibility, χe xxxx(3), for these dyes were ≈2×10−12esu at the very low concentration of 1×10−5moldm−3. The electronic component of molecular hyperpolarizability, γe, was calculated to be ≈1×10−28esu for each dye.