用于Rb蒸气激光泵浦的可调谐窄线宽半导体激光器

由于Rb蒸气的吸收峰随缓冲气体气压存在漂移,利用体布拉格光栅(VBG)实现线宽压窄的同时,实现泵浦半导体激光器中心波长的可调谐也是十分必要的。本文采用国内封装的半导体激光阵列(LDA),利用VBG的温度特性,实现了线宽不大于0.3nm的同时,激光器中心波长从779.89nm到780.35nm可调谐。该激光器可以通过叠阵方式用于Rb蒸气的泵浦和激励。     

浅析元件参数对外腔半导体激光器输出谱宽影响

半导体抽运碱金属蒸气激光器（DPAL）需大功率窄线宽泵浦源,但市售半导体激光器输出线宽远远大于碱金属原子吸收谱宽,难以实现有效泵浦,因此需采用Littrow 外腔法压窄半导体激光器输出谱宽。Littrow 外腔系统中元件参数的选择直接影响大功率半导体激光器输出谱宽。为此文中沿入射光线方向构建外腔压窄模型,利用球面镜替代柱面镜,分析了微柱透镜阵列、光学系统和光栅元件对外腔输出谱宽的影响,模拟结果为微柱透镜阵列焦距越小、光栅刻线越密、球面镜焦距越大,外腔输出谱宽越窄,实验结果符合理论模型。     

窄线宽的外腔半导体激光器

介绍了使用闪耀光栅作为光反馈元件,与原始线宽大于1200GHz的半导体激光器构成的Littrow型外腔半导体激光器,极大地改善了激光器的性能。实验得到了功率恒定、模式单一稳定、线宽优于1.2MHz的激光输出,压窄线宽比为106,并针对Littrow型外腔结构提出了简洁、紧凑的复合型外腔方式。     

A 250 Hz spectral linewidth 1.5 mu m MQW-DFB laser diode with negative-electrical-feedback

A 1.5 mu m corrugation-pitch-modulated MQW-DFB laser diode (LD) with multielectrodes was frequency stabilized using the negative electrical feedback technique. The FM response of the LD was precisely measured and used for the feedback loop design. The FM noise of the LD was reduced and reached 10 Hz/sup 2//Hz at 1 kHz>     

可调谐染料激光的窄谱宽输出

前言 可调谐染料激光器已被广泛地应用于激光光谱学、激光化学、同位素分离、医学和生物学等领域。在全息技术、光通讯、军事等方面染料激光器的应用也在不断扩大。在上述的许多应用中都要求有高的分辨率,而分辨率与激光输出的谱线宽度成反比。因而,如何压窄激光谱线宽度以达到提高分辨率是个很重要的课题。 使用棱镜扩束器的脉冲染料激光器,其优点是光学元件比较经济,准直容易,系统紧凑。适当地选择不同折射率的棱镜及其角度,可使染料激光输     

Conduction cooled narrow linewidth sub-nanosecond multi-beam laser

A conduction cooled high peak power, narrow linewidth, and sub-nanosecond multi-beam laser as an excellent candidate for non-scanning lidar is demonstrated. This laser is based on master oscillator power amplifier (MOPA) scheme which consists of a pulse pumped Nd:YAG/Cr4+:YAG microchip laser as the master oscillator and a high efficient grazing incidence Nd:YVO4 slab amplifier, and the output beam is expanded to 100 mm diameter by a 50× low aberration Galileo beam expander and then divided into a 50×2 staggered arrangement multi-beam array by a diffractive laser splitter. The laser operates at 1 064.28 nm with a spectral linewidth about 20 pm, which generates 1 mJ, 0.78 ns pulses at 7 kHz rate. The fluctuation of output power is less than ±2% when it works continuously for 1 h. The energy uniformity of the 100 sub-beams is up to 90%, the divergence of each sub-beam is about 20 μrad, and the total transmission efficiency of the diffractive laser splitter is more than 85%.     

Analysis of linewidth of separated-electrode DFB laser diode

Presents a new linewidth formula for DFB lasers, which includes the spatial hole burning effect. The linewidth of DFB lasers with three separated electrodes is calculated in various bias conditions. The optimum bias condition is discussed to obtain a narrow linewidth.<>     

6.7 kW全国产化窄线宽三包层光纤激光器

为了实现高功率光纤激光的窄线宽输出,研究了基于大模场三包层掺镱光纤（LMA-YTF）高功率窄线宽光纤激光的热效应和四波混频(FWM)效应。基于FWM效应模型,仿真分析了大模场三包层光纤(LMA-TCF)放大器光谱展宽的影响因素。建立了LMA-YTF的热分布模型,分析了大模场三包层光纤(LMA-YTF)中第二包层功率占比对光纤温度以及泵浦功率上限的影响,讨论了聚合物涂层导热系数和外部温度对光纤温度的影响,实验对比了不同反向合束器的泵浦功率上限,结果表明第二包层功率占比低的(6+1)×1合束器比(9+1)×1合束器拥有更高的泵浦功率上限。基于全国产化器件搭建了一台三包层光纤激光器,实现了输出功率6.7 kW、3 dB线宽为0.32 nm的激光输出。     

高功率窄线宽光纤激光的研究进展与发展趋势

高功率窄线宽光纤激光器具有光束质量好、结构紧凑等优点,在相干合成、光谱合成以及非线性频率变换等领域具有广泛的应用前景,基于窄线宽光纤激光相干合成、光谱合成的激光系统性能指标已经超越单束激光的最高性能,基于窄线宽光纤激光非线性频率变换的激光也实现了同类波段激光的最高性能。分析窄线宽光纤激光功率提升同时保持光束质量过程中产生的物理机制和面临的技术挑战,详细介绍学校课题组在高功率窄线宽光纤激光方面取得的代表性成果,特别是高光束质量的7 kW级非线偏振窄线宽激光和5 kW级线偏振窄线宽激光,不仅是同类激光的最高功率值,也逼近了同等条件下非窄线宽光纤激光的功率极限。根据近年来理论研究和技术攻关结果,结合国内外研究现状,对高功率窄线宽光纤激光未来几个发展趋势进行预判。     

双光纤光栅法-珀腔可调谐窄线宽激光器

基于游标原理,利用一对自由谱宽(FSR)略有不同的光纤布喇格光栅法布里-珀罗腔(FBG-FP)作为模式选择器件,设计了一种新颖的环形腔光纤激光器。从理论和实验上研究了该激光器的特性。通过对可调谐FBG-FP应力调谐,在1552.240～1552.912 nm范围内,以96 pm为平均间距,获得了8个由固定FBG-FP的透射谱所确定的窄线宽稳定激光输出。8个输出波长的平均功率为-17.66 dBm,波动在0.7 dB范围内。当泵浦光的功率为95 mW的时候,输出信号的信噪比均大于50 dB。实验上每隔1 min用光谱分析仪(OSA)对输出光波长自动扫描,记录的输出光波长漂移在数皮米范围内,且功率的波动小于0.1 dB。这种可调谐的窄线宽光纤激光器在光纤通信和光纤传感方面有潜在的应用价值。     

Injection locking of a 1.3 ?m laser diode to an LiNdP4O12 laser yields narrow linewidth emission

A multi-longitudinal-mode InGaAsP laser diode was injection-locked to a low-power LiNdP4O12 laser operating at 1.319 ?m. A net gain of 24 dB was measured with ?28 dBm of injection power. The beat spectrum between the acousto-optically frequency-shifted LiNdP4O12 laser output and the laser diode output displays a 40 dB carrier to pedestal ratio (in 300 kHz bandwidth) under these conditions.     

高效率窄线宽光纤激光器

本文报道了一种环形腔掺饵光纤激光器，得到了泵浦效率高达22.6%，输出线宽小于0.1nm的激光输出。     

CuCl激光器泵浦的高效率窄线宽波导染料激光器

报道一台效率高、线宽窄的波导染料激光器;线宽4GHz,效率12.5％,ASE宽带背景为4.7％,发散角为3mrad。对几种染料谐振腔的输出特性进行了比较。     

A widely tunable narrow linewidth semiconductor fiber ring laser

We have demonstrated a novel approach to obtain a 0.1-nm line width laser with 38-dB sidemode suppression by utilizing a 1.3-μm semiconductor optical amplifier in a fiber unidirectional ring that consists of a linear polarizer and polarization controllers. The laser has a low-threshold current of 22.5 mA as well as a wide tuning range of 28 nm. The new approach is applicable to the 1.55-μm region as well. It is expected that nanosecond wavelength tuning speed is feasible using this approach in conjunction with fast electrooptic polarization controllers, short cavities and low-cavity losses     

1120nm窄线宽掺镱光纤激光器

为了获得窄线宽、高功率、长波长(相对于1030nm~1080nm)的1120nm光纤激光器,采用普通单模掺镱光纤和一对光纤布喇格光栅构建了该光纤激光器的谐振腔,为保证抽运光的完全吸收和避免非线性效应,对有源光纤的最佳长度进行了理论分析和实验验证。结果表明,激光器的阈值抽运功率为40mW、注入抽运功率为265mW时,激光器输出信号光功率35mW,光光转换效率为13.2%,激光器中心波长为1120.9nm,输出激光的谱线宽度为0.03nm。这种激光器的获得是因为采用了高反射率耦合输出光纤布喇格光栅、短谐振腔结构和低功率运转状态。该激光器可作为种子光注入光纤放大器。     

Widely tunable narrow linewidth erbium doped fibre ring laser

An erbium doped fibre ring laser enabling singlemode operation over a continuous wavelength tuning range of 44 nm (1528 nm-1572 nm) with laser linewidths of less than 10 kHz is reported.<>     

Wide continuous wavelength tuning of a narrow linewidth DBR laser

A continuous wavelength tuning range of 5.4 nm is obtained for a three-section DBR (distributed Bragg reflector) laser by applying one control current in both forward and reverse bias directions. In the reverse direction no significant linewidth broadening is seen due to the absence of injection-recombination shot noise, and a linewidth of less than 3 MHz is obtained over a wavelength span of 1.8 nm. The minimum linewidth observed is 580 kHZ     

Effect of phase shift position on spectral linewidth of the π/2distributed feedback laser diode

The dependence of the spectral linewidth on the phase shift position (PSP) of a phase-shifted distributed-feedback (DFB) laser diode is investigated theoretically, using the coupled wave model. In particular, the analysis is performed to find an optimum PSP so as to minimize the spectral linewidth of the laser diode. This optimum PSP is compared to that obtained by maximizing the stability of the laser oscillation. Since both narrow spectral linewidth and good stability are essential for the light source in coherent optical communications, the analysis revealed the suitability of using phase-shifted DFB laser diodes in coherent transmissions     

Narrow linewidth and low chirping characteristics in high poweroperating butt-jointed DBR lasers grown by MOVPE

High power operation in 1.5 μm butt-jointed DBR lasers, made entirely by MOVPE is demonstrated. An output power of more than 30 mW and 60 mW is observed in the CW and pulsed condition, respectively. The minimum spectral linewidth achieved here is 2.1 MHz, at an output power of 12.5 mW and the wavelength chirping width under NRZ modulation is 60-70% of that of conventional DFB lasers     

Extremely narrow linewidth ( approximately 1 MHz) and high-power DFB lasers grown by MOVPE

A suitable structure of narrow linewidth DFB laser is studied experimentally. By thinning the active layer to around 0.07 mu m, controlling kappa L to 1.0, and improving the geometrical uniformity of active region, the linewidth less than 1 MHz is achieved at an output power of around 20 mW in 1.55 mu m DFB lasers with 1.2 mm long cavity length.<>