基于Bi^(3+)Ga^(3+)Al^(3+)共掺高掺铒光纤的短线腔激光器

Short linear cavity laser using high concentration erbium-doped fiber co-doped with Bi^(3+)Ga^(3+)Al^(3+)

短线腔掺铒光纤激光器由环形器(OC)、自制的Bi3+Ga3+Al3+共掺高浓度掺铒光纤(BiGaAl-EDF)、均匀光纤布拉格光栅(UFBG)和波分复用器(WDM)组成。以OC作为全反射腔镜,UFBG为波长选择性部分反射腔镜,利用1 530 nm处吸收系数为84.253 dB/m的BiGaAl-EDF为增益介质,室温下获得了中心波长为1 544.31 nm、边模抑制比(SMSR)大于55 dB的激光输出。分析了BiGaAl-EDF长度对激光器输出特性的影响。结果表明:采用12 cm长的光纤实现了短线腔的窄线宽激光输出,在25 cm长度下,该激光器具有最小的起振阈值和最大的输出功率。测试表明,该短线腔激光器具有线性输出特性,并且其中心波长和输出功率不随时间的变化而发生漂移。

A simple and effective short linear cavity erbium-doped fiber laser was presented.The laser consisted of an optical circulator（OC）,a segment of self-made high concentration erbium-doped fiber co-doped with Bi^3＋Ga^3＋Al^3＋（BiGaAl-EDF）,a uniform fiber Bragg grating（UFBG）,and a wavelength division multiplexing（WDM）.By using the OC as an all-reflection mirror and the UFBG written directly in the G652 fiber as a partial-reflection mirror and a wavelength selector,a stable wavelength oscillation with a center wavelength of 1 544.31 nm and a side mode suppression ratio（SMSR） of about 57 dB is achieved at room temperature.The impact of the length of BiGaAl-EDF on the laser＇s output characteristic was analyzed.With a 12 cm long BiGaAl-EDF as the gain medium,the oscillation output can be realized,and the laser has the minimal oscillating threshold and the maximal output power when the length of BiGaAl-EDF is 25 cm.This laser has a linear output characteristic and its output power and center wavelength do not drift with time.