LBO晶体Ⅱ类相位匹配走离角及互作用长度的计算

Calculation of Type Ⅱ Phase-matching Walk-off Angle and Interaction Length of LBO Crystals

从非线性光学理论出发,数值计算了LBO晶体Ⅱ类相位匹配1064 nm光波倍频的走离角及互作用长度。在全匹配角范围内,1064 nm慢、快两光间夹角的范围是0-1.0°,θ≈0°。Ф≈90°时,夹角为0°;θ≈45°,Ф≈55°时,最大夹角约为1.0°。慢、快两基频光光斑线度相同时,波矢沿θ≈0°,Ф≈88°方向入射时,其互作用长度最大。

From nonlinear optics theory, type II frequency-doubling walk-off angle and interaction length of LBO crystal whose fundamental frequency wavelength is at 1064 nrn were respectively calculated with numerical method . In the range of whole phase-matching angle, the angle range between the slow and the fast lights of 1064 nm is 0-1.0°,θ≈0°.Ф≈90°, the angle is 0°;θ≈45°,Ф≈55°, the maximum angle is approximately 1.0°. When the light-spot dimensions of slow and the fast lights are the same and wave vector incidents along the direction （θ≈0°,Ф≈88） , the interactional length is the maximum.