分别用声光晶体对氩离子激光515 nm谱线作幅度和频率调制,实验研究了碘吸收的差拍饱和吸收信号。用频率调制方法得到斜率极陡的一阶微商饱和吸收信号,并将它作为鉴频曲线把氩离子激光频率稳到127I2分子的P(13)43-0的a3线上。通过与一稳定到相同精细分量上的稳频氩离子激光器拍频,绐出激光频率稳定性优于±4.7×10-12。

A single-mode Ar+ laser at 515nm is modulated in amplitude and frequency by an aoousto-optic modulator respectively, the heterodyne saturation absorption signals in I2 are investigated experimentally. A first derivative-like saturation absorption signal with very steep slope obtained from the FM method is used as a discriminator to stabilize Ar+ laser frequency to hyperflne component a3 of the -P(13) 43-0 of 127I2. With the beat frequency between the stabilized Ar+ laser and other stabilized Ar+ laser stabilized to the same line, the stability of the Ar+ laser is better than ±4.7×10-12.