光纤光梳温度反馈控制方法研究

为了解决光学频率梳长时锁定困难的问题,对光学频率梳重复频率(f_r)与载波相位偏移频率(f₀)的控制方法进行了改进。采用上、下两块半导体制冷片(TEC)对振荡器局部环境进行温度控制,并微调TEC温度将f_r与f₀漂移量分别稳定在10 Hz和600 Hz以内。利用锁相电路反馈控制有效腔长和泵浦光功率对f_r与f₀进行了精密锁定。光学频率梳在170 h时间内连续锁定,f_r与f₀抖动标准偏差分别为0.83 MHz和280 MHz。结果表明,该方法可以实现光学频率梳的长时锁定,增强其环境适应能力。

Study on temperature feedback method of optical frequency comb

In order to solve the problem of long-time operation of a fiber-based frequency comb, the control method of locking the repetition rate (f_r) and carrier envelope phase offset frequency (f₀) of optical frequency comb is improved. Two thermo-electric coolers (TEC), an upper one and an lower one, are used to control the temperature of frequency comb. By adjusting the TEC temperature, the stability of f_r and f₀ can be confined in the range of 10 and 600 Hz, respectively. Then, f_r and f₀ were further stabilized by the feed-back control of the optical path and the pump power, respectively. Finally, in 170-hour operation, the standard deviations of f_r and f₀ were measured as 0.83 and 280 mHz, respectively. The results show that the method can realize the long-term operation of the optical frequency comb and enhance its adaptability to the environment.