飞秒钛宝石光学频率梳的精密锁定

Precise control of femtosecond Ti:sapphire laser frequency comb

经相位锁定后的飞秒钛宝石光学频率梳已经广泛用于绝对光频的测量,这是光频标领域一个革命性的突破.在自建的90MHz飞秒钛宝石激光器的基础上首先采用光子晶体光纤将其光谱展宽到一个光倍频程,接着利用锁相环技术分别将重复频率和载波包络频移同时高精度地锁定到一台稳定度为6×10-14的Cs钟上,进而得到了稳定度相同的飞秒光学频率梳.

Phase controlled Femtosecond Ti：sapphire laser frequency comb have been widely used in measurement of absolute optical frequency, which is the revolutionary progress in the optical metrology. In this paper, based on the home-made 90 MHz femtosecond Ti：sapphire laser, we firstly broadened the spectrum output directly from the laser to more than one octave with a piece of photonic crystal fiber, then locked precisely both the repetition rate and the cartier-envelope phase offset frequency to the same Cs clock with the stability of 6 × 10^-14 by use of two sets of different phase-locked loops. As a result, we obtained the phase controlled Femtosecond laser frequency comb with the stability of the Cs clock.