半导体光放大光纤环形激光器的偏振混沌与相干性

研究了基于半导体光放大器(SOA)的光纤环形激光器的偏振混沌光的特性及其相干性。实验采集激光器的输出功率和偏振度,得到了基于半导体光放大器的光纤环形激光器的输出从自发辐射到受激辐射、再到偏振态混沌激光辐射的演化过程。利用马赫-曾德尔(M-Z)干涉仪验证了混沌激光的相干性,并发现混沌干涉只有零级。测量不同光程差时干涉仪的输出功率,计算相应的干涉条纹可见度,进一步算得混沌激光的相干时间约为40 ps。这一结果与根据光谱计算的该混沌激光的相干时间43 ps基本一致。实验还测得该混沌激光的相干性与半导体光放大器的电流无关。并指出了混沌激光相干应用于低相干光源探测领域的灵敏度和分辨力优势。

The Characteristic of Polarization Chaos and Coherence of Semiconductor Optical Amplifier-Based Fiber Ring Laser

The characteristic of polarization chaos laser and coherence of semiconductor optical amplifier(SOA)-based fiber ring laser are investigated.By detecting the power and degree of polarization(DOP) output of the laser in laboratory,the process from amplified spontaneous emission(ASE) to stimulated emission of radiation,and to polarization chaos laser output is evolved.The coherence of chaotic light is verified employing Mach-Zehnder interferometer,and only the zero-order coherence is observed.Adjusting the optical-path difference of two arms,power output of the interferometer is measured,and visibility of interference streak is computed accordingly.The coherence time of 40 ps is got,which is basically consistent with the time of 43 ps computed by optical spectrum of chaotic laser.It is measured that the chaotic laser's coherence is independent of current of SOA.The superiority of chaotic laser's coherence in resolution and sensitivity is indicated when it is applied in the field of low coherence optical source detection.