Erbium-doped CW and Q-switched fiber ring laser with fiber grating Michelson interferometer

The band-pass characteristic of fiber grating Michelson interferometer is analyzed, which acts as bothband-pass filter and Q-switch. An erbium-doped fiber ring laser based on fiber grating Michelsoninterferometer is implemented for producing single longitudinal mode CW operation with 5 MHz spectrallinewidth and up to 6 mW output power. In Q-switched operation, stable fiber laser output pulses withrepetition rate of 800 Hz, pulse width of 0.6 μs, average power of 1.8 mW and peak power of 3.4 W aredemonstrated. The peak power and average power of the Q-switched pulses are varied with the repetitionrate.     

高精度测量F-P标准具间距的光谱方法

利用高分辨率光谱分析仪对空气隙F P标准具透射谐振峰频率进行测量 ,然后通过直线拟合获得自由谱域 ,从而计算得出F P标准具的间距。对F P标准具间距测量的精度进行分析 ,F P标准具间距测量的相对误差为2× 10 -3 。提出了一种新颖的入射光与F P标准具垂直的精确调节方法     

高功率啁啾高斯脉冲在光纤中传输的形变研究

从光纤广义非线性薛定谔方程出发,定义了用于衡量脉冲形变大小的脉冲形变因子,定量地分析了在传输过程中脉冲形变因子、临界长度、临界功率及初始啁啾之间的关系。结果表明:在传输过程中,当入射脉冲的峰值功率一定时,正啁啾脉冲的形变比负啁啾脉冲和无啁啾脉冲的形变小;当脉冲的初始啁啾一定时,脉冲传输的临界长度随着传输功率的增加而降低,且随着功率的增大,不同初始啁啾脉冲的临界长度趋于一致;在传输距离一定时,临界功率与初始啁啾呈线性变化,且啁啾的漂移对正啁啾脉冲的临界功率影响较大。     

可调谐单频掺镱光纤DBR激光器

对分布布拉格反射(DBR)的透射特性进行了分析,制作了一个单频窄线宽掺镱光纤DBR激光器.在977 nm半导体激光器泵浦下,在1052.5 nm波长处输出功率可达4 mW,线宽小于8 MHz(受测量仪器分辨率限制).采用弧形梁调谐光纤光栅,实现了DBR光纤激光器在单纵模工作状态下的连续调谐,调谐范围可达20.4 nm(1036.1～1056.5 nm),并研究了调谐对激光器的泵浦阈值和斜率效率的影响.     

Single-frequency, single-polarization ytterbium-doped fiber laser by self-injection locking

We demonstrated a stable single-frequency, single-polarization operation of ytterbium-doped fiber laser. As a novel practical method to realize single-polarization operation of fiber distributed Bragg reflector (DBR)laser, we proposed self-injection locking (SIL) with an active fiber ring feedback cavity. The laser has high output power exceeding 15 mW, wavelength of 1053.20 nm, and side-mode suppression ratio greater than 60 dB. The SIL fiber laser shows the improvements in output power and side-mode suppression compared with the fiber DBR laser. No mode-hopping is observed within 2 hours.     

掺镱光纤放大器的实验研究

介绍了利用国产掺镱光纤设计的掺镱光纤放大器的放大特性,分别把单频二极管抽运固体激光器(DPL)和窄线宽的半导体激光器(LD)产生的单频激光注入到掺镱光纤放大器中,对连续信号采用静态和交流调制两种形式进行放大,仅用18m光纤就获得超过26dB的增益。     

Double-pass ytterbium-doped fiber amplifier with high gain coefficient and low noise figure

We have proposed and demonstrated a double-pass ytterbium-doped fiber amplifier using an optical circulator and a fiber Bragg grating as reflector. When the signal has passed through the ytterbium-doped fiber once, it reflects off a 0.2-nm passive fiber Bragg grating filter. This reduces amplified spontaneous emission (ASE) noise from the first pass. The input signal light is amplified both forward and backward through ytterbium-doped fiber. With this double-pass configuration, 1053.15-nm unsaturated signal gain of 28 dB, gain coefficient of 1.1 dB/mW, and noise figure of less than 4 dB are achieved at 977-nm pump power of 68 mW. It is also found that this double-pass configure provides enhancing gain coefficient and improving noise figure by comparison with single-pass configuration.     

Single-frequency,single-polarization ytterbium-doped fiber laser by self-injection locking

We demonstrated a stable single-frequency,single-polarization operation of ytterbium-doped fiber laser. As a novel practical method to realize single-polarization operation of fiber distributed Bragg reflector (DBR) laser,we proposed self-injection locking (SIL) with an active fiber ring feedback cavity.The laser has high output power exceeding 15 mW,wavelength of 1053.20 nm,and side-mode suppression ratio greater than 60 dB. The SIL fiber laser shows the improvements in output power and side-mode suppression compared with the fiber DBR laser.No mode-hopping is observed within 2 hours.     

Multiple-Pulse Operation in Passively Mode-Locked Fibre Laser with Positive Dispersion Cavity

We report the observation of rectangular shape spectrum in passively mode-locked fibre laser with positive dispersion cavity. The spectrum is broad and flat, and 3dB bandwidth can be up to 17.61 nm. Multiple-pulse operation is observed in our laser system. The spectrum width, pulse energy, pulse width and peak power of the mode-locked laser output change with the appearance of multiple-pulse operation.