Push–Pull Carbazole-Based Dyes: Synthesis, Strong Ultrafast Nonlinear Optical Response, and Effective Photoinitiation for Multiphoton Lithography

作者：Michalis Stavrou, Gordon Zyla, Dimitra Ladika, Frédéric Dumur, Maria Farsari, David Gray · 发表于：ACS Applied Optical Materials · 年份：2024 · DOI：10.1021/acsaom.4c00241 · 被引用次数：14 · 研究领域：Nonlinear Optical Materials Studies、Photochemistry and Electron Transfer Studies、Photochromic and Fluorescence Chemistry

High Resolution Image Download MS PowerPoint Slide The present work reports on the ultrafast nonlinear optical (NLO) properties of a series of D−π–Α and D–A push–pull carbazole-based dyes and establishes a correlation between these properties and their efficiency for potential photonic and optoelectronic applications such as multiphoton lithography (MPL). The ultrafast NLO properties of the studied dyes are determined by two distinct experimental techniques, Z -scan and pump–probe optical Kerr effect (OKE), employing 246 fs laser pulses at 515 nm. The results indicate that chemical functionalization of the carbazole moiety with various strong electron-donating and/or electron-withdrawing groups, such as benzene, styrene, 4-bromostyrene, nitrobenzene, trimethyl isocyanurate, methyl, and indane-1,3-dione, can result in a controlled and significant enhancement of the NLO absorptive and refractive responses. In the context of potential applications, the efficiency of carbazole-based organic materials as photoinitiators (PIs) for MPL applications is demonstrated. The fabricated woodpile microstructure using chemically functionalized carbazole as a PI demonstrates improvements in both feature size and MPL efficiency compared to that using unfunctionalized carbazole as a PI. This is attributed to the efficient charge transfer resulting from chemical functionalization, which leads to a substantial increase (approximately 1 order of magnitude) in the values of the imaginary part of th...