提出了一种基于重叠光栅(SIFG)和啁啾光栅(CFBG)的线形腔双波长光纤激光器。激光器采用反射率高于99%的SIFG和带反射率凹陷的CFBG作为波长选择器件,掺铒光纤(EDF)作为增益介质。基于增益均衡技术,激光器通过调节腔内起振双波长处增益与损耗相等抑制模式竞争,实现室温下双波长激射。实验结果表明,本文激光器能够同时输出稳定的1 556.852nm和1 557.680nm双波长激光,线宽小于0.1nm,输出激光的边模抑制比(SMSR)可达15dB,且波长及功率稳定性好;激光器耦合损耗小、结构简单和易于集成,可用于密集波分复用(DWDM)系统、光纤传感等领域。
A new type of dual-wavelength linear cavity fiber laser based on the superimposed fiber grating and chirp fiber Bragg grating (CFBG) is proposed. The fiber laser adopts the superimposed fiber grating whose refleetivity is above 99% and the chirp grating whose refleetivity has sunk place for wavelength selection,and the erbium-doped fiber is used for the gain medium. Based on gain equalization technology, by adjusting the weights on two ends of CFBG, the gain and loss are equal at two wavelengths in the cavity, so as to suppress mode competition and realize double wavelengths lasering at room temperature. The experimental results show that the laser can output stable 1 556. 852 nm and 1 557. 680 nm dual- wavelength lasers at the same time, the line width is less than 0. 1 nm, side mode suppression ratio (SMSR) of the output laser reaches 15 dB,and the stabilities of wavelength and power are very good. The laser coupling loss is small, structure is simple, integration is convenient, so it can be widely used in dense wavelength division multiplexing (DWDM) system and optical fiber sensors.