声光可调谐环形腔掺铒光纤激光器

应用单级偏振无关的准共线型声光可调谐滤波器为调谐元件,实现了环形腔掺铒光纤激光器的连续可调谐激光输出.简要阐述了与偏振无关的准共线型声光可调谐滤波器的工作原理,对其频移补偿原理进行了分析.实验研究得到:当抽运功率为13mW时,中心波长为1550nm的激光输出功率为322μW,阈值抽运功率在7.65mW左右,斜率效率约为6.02%;并获得了38nm带宽(1524.7—1562.4nm)的连续可调谐激光输出.     

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     

基于高双折射Sagnac环的可调环形腔掺铒光纤激光器理论与实验研究

报道了一种利用偏振控制器（PC）和保偏光纤（PMF）组成的高双折射Sagnac干涉环实现选频和调谐的环形腔掺铒光纤激光器.理论模拟了PMF和PC对波长的控制作用.实验中调节PC得到了单波长、双波长和多波长激光;并验证了滤波间隔随PMF长度的变化规律.实验中得到了斜率效率20%,3 dB线宽0.016 nm,30 dB线宽0.097 nm,边模抑制比（SMSR）40 dB左右的稳定激光输出. 关键词： 光纤激光器 Sagnac干涉环 环形腔 掺铒光纤     

A widely tunable dual-wavelength erbium-doped fiber ring laser operating in single longitudinal mode

A new mechanism to induce polarization hole burning effect in Er-doped fiber ring lasers is presented. By using this effect, incorporating with the counter-propagation of the two light beams, the inhomogeneous in the gain medium broadening was significantly increased, and thus a stable dual-frequency Er-doped fiber ring laser operating in single longitudinal mode and single-frequency was demonstrated. Frequency spacing was tunable from 0.47 GHz to THz.     

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)。     

High gain L-band erbium-doped fiber amplifier with two-stage double-pass configuration

An experiment on gain enhancement in the long wavelength band erbium-doped fiber amplifier (L-band EDFA) is demonstrated using dual forward pumping scheme in double-pass system. Compared to a single-stage single-pass scheme, the small signal gain for 1580 nm signal can be improved by 13.5 dB. However, a noise figure penalty of 2.9 dB was obtained due to the backward C-band ASE from second stage and the already amplified signal from the first pass that extracting energy from the forward C-band ASE. The maximum gain improvement of 13.7 dB was obtained at a signal wavelength of 1588 nm while signal and total pump powers were fixed at -30 dBm and 92 mW, respectively.     

掺铒光纤环形激光器混沌带宽特性数值研究

利用掺铒光纤环形激光器非线性克尔效应模型,研究抽运功率和非线性系数对激光器输出混沌信号带宽的影响.研究表明：在非线性系数一定的情况下,混沌带宽随着抽运功率的增加先增大后减小;固定抽运功率为01 W,当非线性系数增加到45 W^-1km^-1时,掺铒光纤激光器输出的混沌带宽达到最大值（153 GHz）,非线性系数继续增加,输出混沌的带宽将逐渐减小. 关键词： 克尔效应 掺铒光纤激光器 混沌 带宽     

Enhancement of pump conversion efficiency in preamplified L-band erbium-doped fiber amplifiers

A new configuration of L-band erbium-doped fiber amplifiers (EDFAs) is presented here. The system contains a double-pass L-band EDFA and an optical preamplifier. Different from conventional preamplified double-pass L-band EDFA systems in which only the forward ASE of the preamplifier is re-used as an auxiliary pump, the new system recycles the backward ASE of the preamplifier as well. Two kinds of main L-band EDFAs are studied, both of which include a section of un-pumped erbium-doped fiber placed in a loop reflector. An improvement of up to 110% in pump conversion efficiency is demonstrated with the proposed recycling of the backward ASE, with respect to the system without recycling.     

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.     

Thermal characteristics of Nd~(3 )-doped fiber ring laser pumped by Ti:sapphire tunable laser

A Nd(3 )-doped fiber ring laser pumped by a CW Ti:sapphire tunable laser is reported. The characteristics of the system are studied for the first time at 77K and 300K. The results show a lower threshold and a higher slope efficiency at 77K than that at 300K. Applications of the Nd~(3 )-doped fiber ring laser in a multiplexing fiber sensor system and a fiber-ring-laser type temperature sensor are discussed.     

A compact graphene Q-switched erbium-doped fiber laser using optical circulator and tunable fiber Bragg grating

We demonstrate a passively Q-switched tunable erbium-doped fiber laser(EDFL)based on graphene as a saturable absorber(SA).A three-port optical circulator(OC)and a strain-induced tunable fiber Bragg grating(TFBG)are used as the two end mirrors in an all-fiber linear cavity.The Q-switched EDFL has a low pump threshold of 23.8 mW.The pulse repetition rate of the fiber laser can be widely changed from 9.3 kHz to 69.7 kHz by increasing the pump power from23.8 mW to 219.9 mW.The minimum pulse duration is 1.7μs and the highest pulse energy is 25.4 nJ.The emission wavelength of the laser can be tuned from 1560.43 nm to 1566.27 nm by changing the central wavelength of the straininduced TFBG.     

一种新型可调谐环型腔掺饵光纤激光器输出特性的研究

理论分析了光纤光栅调谐量与光纤应力和拉伸系数间的关系,实验研究了环行腔掺铒光纤激光器的最佳输出耦合比、调谐波长与新型可调谐光纤光栅挤压长度的关系以及不同耦合比对激光线宽和调谐范围的影响。在最佳输出耦合比为9:1时得到3.8mW最大激光输出功率,在耦合比为7:3时最大调谐范围为7.85nm。     

Thermal characteristics of Nd3+-doped fiber ring laser pumped by Ti:sapphire tunable laser

A Nd(3+)-doped fiber ring laser pumped by a CW Ti:sapphire tunable laser is reported. The characteristics of the system are studied for the first time at 77K and 300K. The results show a lower threshold and a higher slope efficiency at 77K than that at 300K. Applications of the Nd~(3+)-doped fiber ring laser in a multiplexing fiber sensor system and a fiber-ring-laser type temperature sensor are discussed.     

Thermally tunable microfiber knot resonator based erbium-doped fiber laser

A compact and tunable erbium-doped fiber laser is demonstrated using a highly doped fiber and a microfiber knot resonator (MKR) structure which is laid on the surface of a small peltier. The MKR functions as both a reflector and a tunable filter where tunability is achieved by varying the temperature of the resonator by heating the peltier. A stable laser output is achieved at the 1533 nm region with an optical signal to noise ratio (OSNR) of 27 dB using a 65 mW of 980 nm pump power. The operating wavelength of the laser can be tuned from 1532.60 nm to 1533.49 nm as the temperature is increased from the room temperature of 24 to 90 °C. It is observed that the operating wavelength shifts to a longer wavelength as the temperature increases with an efficiency of 12.4 pm/°C. This is due to the thermally induced optical phase shift attributable to the changes in effective refractive index and optical path length of the MKR loop.     

基于偏振保持掺Er3+光纤的高稳定性单波长光纤激光器

研制出光敏偏振保持掺Er³⁺光纤,通过在这种光纤上紫外写入三个光纤光栅,形成对抽运激光高转化效率的谐振腔.在输出功率为23.617dBm、工作波长为976nm的激光抽运下,得到均值功率为9.20dBm、均值中心波长为1554.554nm的单波长激光输出.在室温下800min（约13.3h）的测量时间内,其输出功率的波动为±0.05dB,中心工作波长的波动为±0.0015nm. 关键词： 光纤激光器 3+光纤')" href="#">偏振保持掺Er³⁺光纤 光纤Bragg光栅     

Full L-band coverage of multiwavelength erbium-doped fiber laser

We propose and experimentally demonstrate a dual-pass unbalanced in-line Sagnac interferometer as a novel comb filter for implements in erbium-doped fiber lasers to obtain wide wavebands of multiwavelength radiations with enhancements of signal-to-noise ratios (SNRs). The hybrid combinations of the comb filter with the two schemes of nonlinear polarization rotation and intensity dependent loss have successfully not only enlarged the lasing bandwidth up to 47 nm but also enhanced the SNR up to 40 dB. The simultaneous lasing-wavelengths of 117 channels are also obtained. The multiwavelength lasing spectra with free spectral range of 0.4 nm covering the full L-band are useful for the applications of DWDM and WDM-PON systems.     

Wavelength tunable linear cavity cladding pump Er<Superscript>3+</Superscript>/Yb<Superscript>3+</Superscript>co-doped fiber laser operating in L-band

We have demonstrated a novel tunable linear cavity Er³⁺/Yb³⁺ co-doped fiber laser, which utilizes amplified spontaneous emission as a secondary pump source so that it can operate in L-band. The tuning wavelength range can be up to 34 nm, from 1588.6 to 1622.6 nm, and the output power excursion of the laser at different wavelengths can be less than 0.4 dB by using a two sections of high-birefringence fiber loop mirror as the wavelength filter. The high output power of 200 mW is realized by using the cladding-pump.     

Tunable erbium-doped fiber ring laser for applications of infrared absorption spectroscopy

We fabricate a low noise erbium-doped fiber ring laser that can be continuously tuned over 102 nm by insertion of the fiber Fabry-Perot tunable filter (FFP-TF) in the ring cavity with a novel cavity structure and the optimal gain medium length. As an application of this fiber ring laser, we performed the absorption spectroscopy of acetylene (¹³C₂H₂) and hydrogen cyanide (H¹³C¹⁴N) and measure the absorption spectra of more than 50 transition lines of these gases with an excellent signal to noise ratio (SNR). The pressure broadening coefficients of four acetylene transition lines are obtained using this fiber ring laser and an external cavity laser diode.     

Multiwavelength fiber laser using S-band erbium-doped fiber amplifier and semiconductor optical amplifier

A multiwavelength fiber ring laser that is based on an S-band erbium-doped fiber amplifier (EDFA) and a semiconductor optical amplifier (SOA) is developed. An optical switch is used to switch the multiwavelength fiber laser between S-band and L-band. This fiber laser can stably lase seven wavelengths in the S-band or 28 wavelengths in the L-band. Additionally, the lasing wavelengths with a signal-to-noise ratio of over 33 dB and a wavelength spacing of 100 GHz are demonstrated experimentally. The average powers of the lasing wavelength in the S-band and the L-band are −7.53 and −12.15 dBm, respectively.     

Characteristics of the bandwidth in gain-clamped erbium-doped fiber amplifiers

1.IntYoductionErbium-dopedfiberamplifiers(EDFAs)arepresentlyofgreatinterestinopticalfibercommunicationsystem.Thegainprofiles,thatis,thegainforallwavelengthsofinter-est,areveryimPortantproPertiesofEDFAsinthewavelength-division-multip1exing(WDM)fibersystems['j.Manynumericalandanalyticalmethods(seeforexampleL1jandreferencestherein)canbeusedtoinvestigatethegainprofile8ofEDFAs,buttheyneedcumbersomemeasurementS(forexampIesPectraImeasurementsofEr-dopingabsorWtionandemission,andsoon)andhence…