Zucolotto Cocca Leandro H, Valverde João V P, de Brito Elisa B, de Freitas Jilian Nei, de F Vmarques Maria, Mendonça Cleber R, De Boni Leonardo
Institute of Physics of São Carlos, University of São Paulo, CP 369, São Carlos-SP 13560-970, Brazil.
Photonics Group, Instituto of Physics, Federal University of Goias, Goiânia-GO 74690-900, Brazil.
ACS Omega. 2025 Apr 16;10(16):16539-16547. doi: 10.1021/acsomega.4c11627. eCollection 2025 Apr 29.
In recent years, conjugated polymers have garnered significant interest due to their versatile optical and electronic properties, including low band gaps and strong absorption in the visible and near-infrared regions. These features, combined with high molar absorptivity and notable photoluminescence and electroluminescence quantum yields, make these materials highly suitable for applications in optoelectronics, nonlinear optics, and other advanced photonic technologies. This study investigates the linear and nonlinear optical properties of three fluorene-benzothiadiazole-based copolymers-, , and -differentiated by their electron-accepting units and polymer chain lengths. Through comprehensive spectroscopic analysis, including one-photon absorption, fluorescence emission, and multiphoton absorption studies, as well as quantum chemical calculations, the research provides insights into how molecular design can be optimized for nonlinear optical performance. The results reveal significant two-photon absorption cross sections and demonstrate the potential of these materials for multiphoton-excited fluorescence and optical limiting applications.
近年来，共轭聚合物因其多功能的光学和电子特性而备受关注，这些特性包括低带隙以及在可见光和近红外区域的强吸收。这些特性，再加上高摩尔吸光率以及显著的光致发光和电致发光量子产率，使得这些材料非常适合用于光电子学、非线性光学和其他先进光子技术。本研究调查了三种基于芴-苯并噻二唑的共聚物（、和，它们因电子接受单元和聚合物链长度不同而有差异）的线性和非线性光学特性。通过全面的光谱分析，包括单光子吸收、荧光发射和多光子吸收研究，以及量子化学计算，该研究为如何针对非线性光学性能优化分子设计提供了见解。结果揭示了显著的双光子吸收截面，并证明了这些材料在多光子激发荧光和光学限幅应用方面的潜力。
