可调谐环形腔掺铒光纤激光器

使用高掺杂掺铒光纤制成了低噪声的环形腔光纤激光器。通过对文献中报道的环形腔结构光纤激光器输出的分析,指出了其存在的问题,并提出了减小其输出背景噪声的改进方案。通过实验验证了改进后的环形腔结构的低噪声特点,从原理上进行了解释。用不同掺铒光纤长度、泵浦功率、光栅波长及光栅反射率进行了实验,得到它们对输出光的性能影响。这种环形腔结构的光纤激光器可实现1525nm~1565nm连续可调谐输出。     

环形掺铒光纤激光器输出特性的理论研究

通过求解速率方程,建立了环形掺铒光纤激光器的理论模型.获得了激光器的阈值泵浦功率、输出功率.斜率效率以及最佳掺铒光纤长度的解析解.对结果给予了清晰的物理解释     

全光纤色散腔掺铒光纤激光器

报道用９７１ｎｍ半导体激光器泵浦的掺铒光纤激光器的一些实验研究结果。演示了由光纤环反射器和光纤光栅构成的全光纤色散掺铒光纤激光器，在１．５５μｍ波段获得了线宽小于０．０５ｎｍ的激光输出。     

线形腔掺铒光纤激光器输出特性的理论研究

通过求解速率方程，从理论上详细地分析了形腔掺铒光纤激光器输出特性，得到了稳定条件下激光器阈值泵浦功率，输出功率和斜率效率的解析表达式；给出了构造线形腔掺铒光行激光器所需掺铒光纤最短长度和最佳长度的表达式。     

低噪声环形腔掺铒光纤激光器的研究

分析了环形腔掺铒光纤激光器的输出特性,给出了稳态下的激光器输出功率、阈值泵浦功率和斜率效率的解析表达式,为激光器结构的优化提供了依据。搭建了全保偏环形腔掺铒光纤激光器,利用未泵浦铒纤中由驻波干涉和饱和吸收诱发的自写入光纤光栅的窄带滤波特性及反射波长的自适应特性,有效地解决了激光器的跳模问题。通过测量得到激光器系统的泵浦阈值为15.3mW,斜率效率为2.8%,输出偏振度为32dB。利用非平衡光纤干涉仪系统和相位产生载波(PGC)调制解调技术测得激光器的相位噪声为3×10-5rad/Hz~1/2(1kHz)。     

稳定可调谐的单纵模多环形腔掺铒光纤激光器

提出了一种多环形腔(MRC)结构的稳定可调的单纵模(SLM)掺铒光纤激光器,多环形腔结构由双环形有源腔和两个次级无源腔组成.这种激光器是利用光纤法布里珀罗可调滤波器(FFP-TF)以及光学光栅滤波器(OGF)两种滤波器和多环形腔结构相结合来共同选模.可实现波长调节范围为1528～1565 nm,在整个波长调节范围内边模抑制比大于44.53 dB,在1554 nm附近边模抑制比可以达到最大值51.18 dB, 输出功率为-8.84 dBm,通过应用多环型腔结构,激光器的输出很稳定,在18 min的观察时间内,中心波长的变化小于0.02 nm,输出功率的变化小于0.04 dBm,实现了稳定且可调谐的单纵模输出.     

可调谐锁模脉冲环形腔掺铒光纤激光器

报道了一种结构简单、波长稳定可调的被动锁模环形腔掺铒光纤激光器.利用非线性偏振旋转效应作为等效可饱和吸收体实现自起振被动锁模,通过使用光纤偏振控制器和偏振相关光隔离器作为波长调谐器件,在输出端使用输出耦合器为工作波长在1550±50 nm的宽带耦合器,实现了光纤激光器的输出锁模脉冲激光中心波长较宽范围可调谐.实验上获得了低阈值自起振,重复频率为10.23 MHz,中心波长在1548.64～1600.24 nm内连续可调,边模抑制比大于44 dB的超短脉冲输出.     

Sagnac干涉仪与光纤环形激光器

依据相干光学理论,以现代激光干涉侧试技术中的光纤Ｓａｇｎａｃ干涉仪为例,分析和讨论了光纤环形激光器的基本工作原理,并结合其物理原理简要介绍了光纤环形激光器和光纤陀螺（ＦＯＧ）的应用的发展前景。     

可调谐光纤环形腔激光器输出特性的理论与实验研究

提出一种简单的理论模型,并通过数值模拟详细研究了可调谐光纤环形腔激光器的输出特性随掺铒光纤长度、输出耦合比、抽运功率、腔内损耗等参量的变化关系.理论分析得到,通过参量优化可以实现在铒离子增益范围内超过130nm带宽(1500—1630nm)的激光输出.实验获得了100nm带宽(15185—16185nm)的可调谐激光输出,激光器输出功率高,信噪比在大部分可调范围内高于60dB,实验结果与理论分析符合得较好 关键词： 掺铒光纤 光纤环形腔激光器 可调谐 光纤珐布里珀罗滤波器     

掺铒光纤环形激光器输出特性的研究

根据掺铒光纤激光器的速率方程，对环形腔光纤激光器的输出特性进行了理论分析，得到了光纤激光器在稳态条件下阈值抽运功率、激光输出功率和斜率效率的解析表达式。利用数值模拟结果对光纤激光器的这些基本特性参量进行了分析和讨论，为光纤环形激光器的优化设计提供了依据。并进行了980nm抽运的掺铒光纤激光器的实验，实验证明理论分析得到的基本特性是合理的。     

Switchable multi-wavelength erbium-doped fiber ring laser based on cascaded polarization maintaining fiber Bragg gratings in a Sagnac loop interferometer

A switchable multi-wavelength erbium-doped fiber (EDF) ring laser based on cascaded polarization maintaining fiber Bragg gratings (PMFBGs) in a Sagnac loop interferometer as the wavelength-selective filter at room temperature is proposed. Due to the polarization hole burning (PHB) enhanced by the PMFBGs, stable single-, dual-, three- and four-wavelength lasing operations can be obtained. The laser can be switched among the stable single-, dual-, three- and four-wavelength lasing operations by adjusting the polarization controllers (PCs). The optical signal-to-noise ratio (OSNR) is over 50 dB.     

Switchable erbium-doped fiber ring laser based on Sagnac loop mirror incorporating few-mode high birefringence fiber

Without the need of any other additional filtering device, a triple-wavelength switchable erbium-doped fiber ring laser based on Sagnac loop mirror incorporating a piece of few-mode high birefringence fiber is newly proposed and experimentally demonstrated. Three potential lasing wavelengths at about 2.0 nm interval with the side mode suppression ratio higher than 40 dB can be switched mainly by adjusting a polarization controller next to the few-mode high birefringence fiber in the Sagnac loop. In addition to the stable single-line lasing operation, simultaneous dual- and triple-line oscillations are also highly stable at room temperature with suppressing the intrinsic homogeneous gain broadening of the erbium-doped fiber.     

Switchable dual-wavelength erbium-doped fiber-ring laser based on one polarization maintaining fiber Bragg grating in a Sagnac loop interferometer

A switchable erbium-doped fiber-ring laser providing dual-wavelength outputs with orthogonal polarizations when operating at room temperature is proposed. One polarization-maintaining fiber Bragg grating (PMFBG) in a Sagnac loop interferometer is used as the wavelength-selective filter. Due to the enhancement of the polarization hole burning (PHB) by the PMFBG, the laser can be designed to operate in stable dual-wavelength or wavelength-switching modes with a wavelength spacing of 0.336 nm at room temperature by adjusting a polarization controller (PC). The optical signal-to-noise ratio (OSNR) is over 42 dB. The amplitude variation over 90 min is less than 0.6 dB for both wavelengths.     

Wavelength tunable erbium-doped fiber ring laser operating in L-band

We describe a novel erbium-doped fiber ring laser utilizing the backward amplified spontaneous emission (ASE) power as a secondary pump source so that it can operate in L-band stably. The output wavelength can be tuned in a wide range of 45 nm, from 1560 to 1605 nm. We also compared this scheme with the condition of not using the ASE as secondary pump source, and found this scheme could improve the performance of the laser when using the same components.     

基于二阶保偏光纤Sagnac环光纤激光器的振动检测研究

提出了一种可用于振动检测的新型光纤光栅传感技术. 用偏振控制器和高双折射保偏光纤构建成Sagnac环, 结合掺铒光纤、单模光纤和隔离器, 形成了单波长光纤激光器, 由粘有光纤Bragg光栅的悬臂梁作为传感探头, 并利用Sagnac环本身的线性边缘, 解调振动信号. 阐述了Sagnac环原理及其产生的边缘效应, 并进行了数值模拟计算, 对振动信号进行了检测实验, 检测系统从L₁到L₁+L₂之间对应的周期可调, 灵敏度高达38.2 μ W/nm, 线性度为0.9996, 动态范围在40–70 dB, 可满足振动传感检测的技术参数要求. 关键词： 光纤光学 振动检测 保偏光纤Sagnac环 光纤激光器     

基于FLM的L波段双波长EDFL的双稳态变换

提出和验证了一种L波段双波长掺铒光纤激光器(EDFL)双稳态控制变换和双波长开关切换的方法.将偏振控制器(PC)插入基于3 dB光纤耦合器的光纤环镜(FLM)中，并将该FLM用作L波段双波长级联线形耦合腔EDFL的公共腔镜，结果表明，调节PC可以改变FLM的反射率，实现对EDFL双稳态特性的有效控制，且双稳态特性随FLM反射率呈单调变化.利用这一性质，提出并证实，对于处在FLM最大反射率对应的双稳态第一跃变点和最小反射率对应的双稳态第二跃变点之间的任意固定抽运光功率，调节PC可实现两个稳态之间的相互变换和双波长之间的相互切换.     

Tunable dual-wavelength fiber laser based on a single fiber Bragg grating in a Sagnac loop interferometer

We propose a simple dual-wavelength Er-doped fiber laser configuration based on a dual-wavelength fiber Bragg grating written on the splice joint between two different fibers for wavelength-selective filter in the Sagnac loop interferometer. The wavelength separation between the adjacent lasing wavelengths is 1.12 nm and the side-mode suppression ratio (SMSR) is over 55 dB. The output power variation is less than 0.8 dB over a two-minute period. Moreover, the lasing wavelength can be effectively tuned using the thermal heating method.     

Broadly tunable dual-wavelength erbium-doped ring fiber laser based on a high-birefringence fiber loop mirror

A broadly tunable dual-wavelength erbium-doped ring fiber laser based on a high-birefringence fiber loop mirror (HiBi-FLM) and a polarization controller is demonstrated experimentally. The measured transmission spectrum of HiBi-FLM covers a wide range from 1525 to 1575 nm. The wavelength of proposed laser can be flexibly tunable during this range of ∼50 nm by adjusting the polarization controller. In addition, the spacing of two wavelengths is adjustable by changing the length of HiBi fiber. The dual-wavelength lasers with the HiBi fiber length of 1 and 2 m are experimentally demonstrated and compared. The experimental results show that the proposed laser can stably operate on two wavelengths simultaneously at room temperature, and the output peak power variation is about 0.5 dB during 40 min.