Experimental optimization of an erbium-doped super-fluorescent fiber source for fiber optic gyroscopes

Double-pass forward and double-pass backward erbium-doped super-fluorescent fiber sources(EDSFSs) were combined in one configuration.A 980 nm laser diode pumped the same erbium-doped fiber from both directions using a coupler as a power splitter.The double-pass configuration was achieved by coating the fiber end face.Firstly,an optimal fiber length was found to obtain a high stability of output light wavelength with pump power, and then 1530/1550 nm wavelength division multiplexing was used for spectrum planarization,which expanded the bandwidth to more than 22 nm.The final step was a test of temperature stability.The results show that the rate of the central wavelength change kept to below 3.5 ppm/℃in the range of -40 to 60℃and 1-2 ppm/℃in the range of 20-30℃.Considering all the three factors of the fiber optic gyro applications,we selected 80 mA as the pump current,in which case the central wavelength temperature instability was calculated as 2.70 ppm/℃, 3 dB bandwidth 22.85 nm,spectral flatness 0.2 dB,output power 5.17 mW and power efficiency up to 9.92%.This experimental result has a significant reference value to the selection of devices and proper design of ED-SFSs for the application of high-precision fiber optic gyroscopes.     

抗中子辐射加固超辐射发光二极管的研究

我们设计并制作了一种高性能的抗中子辐射的超辐射发光二极管。高能中子辐射后产生的位移损伤造成器件有源区内少子寿命减少,从而导致器件光输出功率的降低。通过理论分析可知高输出功率的超辐射发光二极管对中子辐射的敏感度较低。本文中的超辐射发光二极管的有源区采用了具有高量子效率和小体积有源区的InGaAsP/InP多量子阱结构,外延波导层采用了线性缓变折射率分别限制结构(GRIN-SCH),并设计和优化出了特殊波导吸收区和腔面减反射膜结构。辐射实验结果显示,在中子注量为6?10₁₃～1?10₁₄n/cm₂(1MeV)下,InGaAsP/InP多量子阱结构的超辐射发光二极管与双异质结结构相比具有更好的抗中子辐射性能。     

光纤陀螺用掺铒光纤超荧光光源的优化设计

本文通过光功率分配器仅用一支980 nm激光器对同一段掺铒光纤进行双向泵浦,且通过在光纤端面镀膜实现光源双程化,将双程前向和双程后向结构结合在一种结构中。首先初步优化光纤长度,获得输出光波长随泵浦功率的高稳定性,之后采用1530/1550光波分复用器进行光谱平坦处理,拓展带宽到大于22 nm,并在此基础上做温度稳定性实验,结果显示,在0～60 ℃温度范围内,中心波长稳定性保持在4 ppm/℃以下,在20～30 ℃范围内,波长稳定性可达1～2 ppm/℃。综合考虑光纤陀螺应用需要的三个指标,实验优化得泵浦电流为80 mA时,光源中心波长温度稳定性计算为2.70 ppm/℃,3dB带宽为22.85 nm,光谱平坦度为0.2 dB,输出功率为5.17 mW,此时功率效率为9.92%。该工作条件对满足高精度光纤陀螺有很好的参考价值。