光纤飞秒光梳频率精密控制的研究

Precise control of fiber-based femtosecond optical frequency comb

新一代光纤飞秒光梳在精密测量和基础物理研究领域中有着广阔的前景,一种通过数字电荷泵锁相环和温控电路相结合的方法可以精密控制光纤飞秒光梳。成功搭建了光纤飞秒光梳系统。光梳的重复频率为129 MHz,初始频率大约为33 MHz。通过自主研发的温控和数字电荷泵锁相环成功地把光纤飞秒光梳锁定在了由Agilent PSG Analog Singal Generator提供的标准微波信号上,锁定时间至少长达1天。锁定后重复频率的抖动标准差为0.78 mHz,与基准源同一个数量级且很接近,锁定后初始频率的抖动标准差达8.98 Hz。

The fiber-based femtosecond optical frequency comb has great potential in the field of fundamen- tal physics and precision measurement. An experimental apparatus for precise control of the fiber-based femtosecond optical frequency comb was discribed. The system was combined with a digital charge-pump phase-locked loop （CPPLL） and a temperature stabilizer. The optical comb system was buit of which the repetition frequency Frep is 129 MHz and the carrier-envelope offset （CEO） frequency Fceo is about 33 MHz. The frequency comb was locked with the standard signal provided by the agilent PSG analog signal gen- erator. The locked state can be maintained over 1 day. The standard deviation of repletion frequency was 0.78 mHz which is the same order of magnitude with reference, and the standard deviation of CEO frequency can be 8.98 Hz.