Theoretical Study And Simulation Of 589 Nm Radiation Generated By Sum Frequency Generation

589 nm radiation generated by sum frequency generation has potential applications in many fields, such as high-power and high-energy laser propagation in atmosphere, astronomical observation and laser medicine, etc. Adaptive optics is usually required to compensate the aberration in high power laser propagation in atmosphere, which needs an effective optical beacon. Sodium optical beacon is considered the most effective one. Theoretical study and simulation of 589 nm radiation generated by sum frequency generation (SFG) of 1064 nm and 1320 nm lasers is analyzed in this thesis, which is important for high efficient sum frequency generation experiment in the future. Sum frequency is a three-wave interaction process. From the coupled wave equations and the phase-matching conditions, the high efficiency sum frequency method is proposed. The expression of nonlinear susceptibility tensor for sum frequency generation is derived based on the structures and the optical characteristics of the biaxial crystals KTP and LBO. The nonlinear susceptibility matrix is modified for sum frequency generation and is validated in the second harmonic generation applications. The phase matching conditions for sum frequency generation are analyzed. The optimum phase matching angles and effective nonlinear coefficients for KTP and LBO are derived and calculated. The power conversion of sum frequency generation with the different ratio of the fundamental photon numbers is simulated and the dependence of power density with the crystal-lengths is discussed. The acceptance parameters of biaxial crystals KTP and LBO are calculated and the non-critical phase matching (NCPM) conditions are also given. Based on the theoretical study and simulation results, the high efficient bow-tie resonator for sum frequency generation is proposed and the preliminary experiment is carried out.