Third-Order Optical Nonlinearity in Schiff-Base Liquid Crystal with Naphthalimide
Niu Ruimin Zhu Xiaorong Sun Zhenrong(Key Laboratory for Optical and Magnetic Resonance Spectroscopy, Department of Physics, East China Normal University, Shanghai 200062)Zhang Yingchao Su Jianhua Tian He(Institute of Fine Chemicals, East China University of Science and Technology, Shanghai 200237)(Received 29 January 2002; revised 5 April 2002)
By using Nd∶YAG mode locked pulse laser (λ=532 nm, τ 0=35 ps), the third order nonlinear optical susceptibility χ (3) , and time response properties of liquid crystals containing Schiff base and Naphthalimide are measured with forward degenerate four wave mixing (DFWM). The corresponding nonlinear refractive index coefficient n 2, second hyperpolarizability γ (3) are calculated. The mechanism for their nonlinear effect is discussed.