基于飞秒光纤激光器的光频率梳设计与研制技术

Design and Development Technique for Optical Frequency Comb Based on Femtosecond Fiber Lasers

提出了一种基于飞秒光纤激光器的光频率梳设计与研制技术。设计与研制出脉冲宽度为55fs、频率为210 MHz的色散管理孤子锁模掺铒光纤激光器,并优化设计了啁啾脉冲光纤放大链路;由负色散高非线性光纤产生了频率范围为1080~2320nm的倍频程超连续谱,经f-2f(f为频率)自差拍检测出信噪比达32dB的载波包络偏移频率;通过将重复频率的4次谐波和载波包络偏移频率锁定到商用铷原子钟,实现了对光频率梳的高精度锁定。测量结果表明,1s计数门控时间下的重复频率和偏移频率标准偏差分别为0.65mHz和1.76mHz,100s采样时间下的Allan偏差分别为1.74×10^(-13)和1.80×10^(-11)。这种光纤光梳可望满足光频计量、光梳光谱、时频传递和微波产生等领域的应用需求。

A design and development technique for optical frequency comb based on femtosecond fiber laser is proposed. A dispersion-managed solution mode-locked erbium-doped fiber laser with pulse width of 55 fs and frequency of 210 MHz is designed, and the chirped pulse fiber amplification link is optimized. An octave supercontinuum from 1080 nm to 2320 nm is generated by a fiber with high nonlinear, which makes the signal-to- noise ratio of the detected carrier-envelope offset frequency reach 32 dB hy the f-2f （f represents frequency） autodyne method. When the 4th harmonic wave of repetition rate and the carrier envelope offset frequency are locked to a commercial rubidium atomic clock, an optical frequency comb is locked with high precision. Measurement results show that the standard deviations of repetition rate and carrier envelope offset frequency are 0.65 mHz and 1.76 mHz at 1 s counter gate time, corresponding to the Allan deviations of 1.74×10-13 and 1.80×10-11 for 100 s sampling time, respectively. Such a fiber optical comb may meet applications in fields of optical frequency metrology, optical comb spectroscopy, timing and frequency transfer, microwave generation and so on.