Low power laser induced third-order nonlinear optical (TNLO) parameters of Schiff base molecule (E)-N'-(4-(dimethylamino)benzylidene) isonicotinohydrazide (ISB), is synthesized and characterised by UV-Visible, FT-IR, ¹H NMR, ¹³C NMR and mass spectroscopy techniques. The effect of polar solvents on linear features and TNLO features of ISB are examined. TNLO properties of ISB are studied via low power Z–scan method, using a diode laser working at 650 nm wavelength. Self-defocusing, saturable absorption (SA) and reverse saturable absorption (RSA) based optical nonlinearities are observed. The order of nonlinear index of refraction (n₂) and nonlinear coefficient of absorption (β) of ISB is found to be10⁻⁷ cm²/W and 10⁻³ cm/W, respectively. The β of ISB has switchover from SA to RSA by increasing the solvent polarizability. Furthermore, the TNLO susceptibility (χ⁽³⁾) of ISB increases with increase in solvent dipole moment. Due to its exceptional optical features; ISB serves as an ideal nonlinear optical material for photonics and optoelectronics applications.

低功率激光诱导的席夫碱分子 (E)-N'-(4-(二甲基氨基)亚苄基) 异烟酰肼 (ISB) 的三阶非线性光学 (TNLO) 参数, 被合成并通过紫外-可见、傅立叶变换红外、¹ H NMR、¹³ C NMR 和质谱技术。考察了极性溶剂对 ISB 的线性特征和 TNLO 特征的影响。ISB 的 TNLO 特性通过低功率 Z 扫描方法研究，使用工作在 650 nm 波长的二极管激光器。观察到基于自散焦、可饱和吸收 (SA) 和反向可饱和吸收 (RSA) 的光学非线性。发现ISB的非线性折射率(n ₂ )和非线性吸收系数(β)的阶数为10 ⁻⁷ cm ²/W和10 ^-3  cm/W，分别。ISB 的 β 通过增加溶剂极化率从 SA 转换为 RSA。此外，ISB 的 TNLO 磁化率 (χ ⁽³⁾ ) 随着溶剂偶极矩的增加而增加。由于其卓越的光学特性；ISB 是光子学和光电子学应用的理想非线性光学材料。