Li Feng, Zhang Aiqin, Feng Xinhuan, Wai P K A
Opt Express. 2013 Dec 16;21(25):30255-65. doi: 10.1364/OE.21.030255.
In a harmonically mode locked laser, the supermode noise peaks in the RF spectrum can be observed directly because they are separated from the driving frequency and its harmonics of the active mode locker. Using a simple theoretical model, we showed that the intensities of the supermode noise peaks will decrease if the coherence of the laser output decreases. We harmonically mode locked a Fourier domain mode locked (FDML) fiber laser to the third order. We observed that the supermode noise peak intensities decrease significantly when the detune between the sweeping frequency of the tunable filter and the cavity resonant frequency increases. It is therefore possible to use the supermode noise peaks to monitor the frequency detune of the tunable filter for auto-calibration of FDML fiber lasers.
在谐波锁模激光器中，可以直接观察到射频频谱中的超模噪声峰值，因为它们与有源锁模器的驱动频率及其谐波是分开的。通过一个简单的理论模型，我们表明，如果激光输出的相干性降低，超模噪声峰值的强度将会减小。我们将一个傅里叶域锁模（FDML）光纤激光器谐波锁模到三阶。我们观察到，当可调谐滤波器的扫描频率与腔谐振频率之间的失谐增加时，超模噪声峰值强度会显著降低。因此，可以利用超模噪声峰值来监测可调谐滤波器的频率失谐，以实现FDML光纤激光器 的自动校准。
