Synthesis And Two-Photon Optical Limiting Properties Of Cyclopentane Dyes And Pyridinium Salt Dyes

Optical limiting materials based on two-photon absorption (TPA) have great application values on ultra-fast laser protection. Thus, to design and explore materials with large TPA coefficient is a very significant work. Normally, TPA coefficients of materials can be improved via increasing TPA cross-sections or concentrations of functional chromophores in materials. The purpose of this thesis is to develop TPA optical limiting materials for 1064 nm ultra-fast laser. Four methylene cyclopentane dyes S1-S4 and five trans-stryryl pyridinium salt dyes R1-R5 were designed and synthesized. Their photophysical properties were studied systematically. Especially, their optical limiting behavior at 1064 nm were investigated using Ti:sapphire femtosecond laser as exciting light source. Some valuable results were achieved.1. A series of novel dicyanomethylene cyclopentane dyes S1-S4 were synthesized by changing the electron donating group in their molecular structures. Their photophysical properties were studied systematically. It is shown that the strength of these electron donating groups is in the sequence: diphenylamino< dimethylamino