光纤激光器技术

在概述光纤激光器基本原理、主要特性及其多种分类方法的基础上,首先介绍了双包层光纤激光器的工作原理和最新进展。通过对几种典型实验装置的分析阐述了光纤激光器的多波长产生机制。并详细讨论了光纤激光器产生锁模脉冲的三种技术：采用振幅或相位调制器的主动锁模技术、利用非线性效应的被动锁模技术以及混合锁模技术,最后比较了这三种技术和实验装置的优缺点并介绍了它们的最新发展情况。     

锁模光纤激光器的研究进展

锁模光纤激光器因其紧凑小巧、成本低和光束质量好等优点,近年来获得了快速发展。根据锁模原理可将锁模光纤激光器分为三类:主动锁模光纤激光器、被动锁模光纤激光器、主被动混合锁模光纤激光器。本文对各类锁模光纤激光器的关键技术和研究进展作了较为详细的介绍,并展望了其应用前景。     

主动谐波锁模掺铒光纤环形激光器调制特性研究

分析了 L i Nb O3 电光强度调制器的非线性调制特征 ,论述在主动谐波锁模掺铒光纤环形激光器 (AHML- EDFL)中利用该调制器的非线性来获取高阶锁模脉冲的物理机理和调制方法。在实验上 ,通过多种非线性调制手段 ,从 AHML- EDFL中获取了分频 ,2阶 ,3阶等高阶锁模脉冲序列。     

光纤激光器锁模技术研究进展

锁模光纤激光器能够产生超短脉冲,在众多领域中有着广泛的应用前景。概述了光纤激光器锁模实现技术的基本原理、典型结构和最新研究进展,分析了主动锁模、被动锁模和混合锁模技术的优缺点,并对多波长锁模、拉伸脉冲锁模和基于光子晶体的锁模光纤激光器的最新研究情况进行了介绍和分析。展望了锁模光纤激光器研究的发展方向和急需解决的问题。     

主动锁模光纤环激光器的研究

本文在阐述了主动锁模光纤环激光器的锁模原理与锁模脉冲生成机制的基础上,进一步论述了阻碍主动锁模光纤环激光器实用化的两种稳定性问题,并提出了一些相应的解决方案。     

主动锁模光纤环激光器的研究

本文在阐述了主动锁模光纤环激光器的锁模原理与锁模脉冲生成机制的基础上，进一步论述了阻碍主动锁模光纤环激光器实用化的两种稳定性问题，并提出了一些相应的解决方案。     

主动锁模光纤激光器的锁相稳定方法

对主动锁模光纤激光器的锁相环路进行了改进,提出一种通过使用"变带宽锁相环"来改善主动锁模光纤激光器稳定性的方法.该方法主要依据信号误差电压实时控制环路的带宽,使环路带宽随锁定信号的频率差动态改变,以达到快速锁定信号的目的,从而提高锁模光纤激光器输出光脉冲的频率稳定性.利用Matlab软件的Simulink功能模块对其实效性进行了仿真验证.结果表明,采用该方法,锁相环的捕捉性能和跟踪性能提高了,主动锁模光纤激光器的工作稳定性得到进一步改善.     

2.8 μm中红外同步泵浦锁模光纤激光器

2.8μm波段中红外光纤激光器在激光医疗领域具有重要的应用,受到广泛关注。研究并实现了2.8μm同步泵浦锁模脉冲光纤激光器。自主研制了大功率单模976nm皮秒脉冲激光器并以此作为泵浦源,以掺铒氟化物光纤环形腔作为谐振器,通过纤芯同步泵浦的方式,在交叉相位调制作用下实现了2.8μm同步泵浦锁模脉冲激光器的制备。锁模脉冲的中心波长为2784.7nm,重复频率为6.534 MHz,脉冲宽度接近光电探测器极限。所提方案不需要在谐振器内插入任何中红外主动或被动调制器,具有系统稳定性好和易于实现全光纤化等优势。     

波长可调谐光纤激光器

已成功研制了一台大功率宽调谐范围光纤激光器,利用主动锁模技术实现了光纤激光器的稳定脉冲输出。实验中调节偏振控制器到合适位置和调制器偏压为3．8V时,获得了平均输出功率2．160mW,重复率9．970754GHz,中心波长为1561．200nm的锁模脉冲输出,输出脉冲中心波长在1528．015-1571．330nm之间连续可调。     

判定声光调制器声场状态的实验方法

目前,激光器声光主动锁模主要使用驻波型声光调制器,调制器的工作状态对模式锁定与锁模脉冲有显著的影响。本文以只Raman-Nath型调制器为例提出几种判定声场驻波状态的实验方法。     

Study on the chaotic dynamics of the mode-locked fiber ring laser

In this paper, we study the chaotic dynamics of the mode-locked fiber laser by numerical simulation. The structures of the passively mode-locked fiber laser and the actively mode-locked fiber laser are studied by modeling and analysis. By appropriately adjusting the small signal gain of the optical fiber amplifier, we observe the period-doubling bifurcations and route to chaos in the passively mode-locked fiber laser based on nonlinear polarization rotation effect. Chaos in the actively mode-locked erbium-doped fiber laser is obtained by adjusting the elliptic modulus parameter of the active modulator and the intra-cavity length. Simulation results have theoretical significance for the practical application of chaotic soliton communication.     

Higher order FM mode locking for pulse-repetition-rate enhancementin actively mode-locked lasers: theory and experiment

We present a novel higher order FM mode-locked technique for active mode-locked lasers which utilizes the higher order sidebands generated by an intracavity phase modulator to establish the mode locking. The resulting mode-locked output exhibits an enhancement of the pulse repetition rate over the modulation frequency by an integral multiple. The higher order FM mode locking is studied theoretically in a laser with a homogeneous gain medium, and simple analytical expressions are obtained to characterize the output pulses. It is shown that the scheme not only enhances the pulse repetition rate but also ensures chirp-free pulses and is effective in eliminating the output pulse phase-state instability, which are commonly observed in conventional FM mode-locked lasers. The effect of group velocity dispersion and cavity nonlinearity is also investigated through numerical solution of the self-consistency equation applied to a fiber ring laser. Finally, detailed experimental results on repetition rate enhancement in fiber lasers are presented and shown to be in good agreement with the theoretical results     

调Q及连续掺Yb光纤激光器中的自锁模研究

在用半导体激光器抽运的单包层掺Yb调Q光纤激光器中观察到了清晰稳定的自锁模脉冲序列。脉冲包络形状为调Q脉冲。每个锁模脉冲的幅值由其在调Q脉冲中的相应位置决定。经过分析，认为自相位调制是调Q光纤激光器中产生锁模的主要原因。自相位调制的存在使得光脉冲的频谱被展宽，当这种展宽和腔的模式间隔相差不多时，腔内的模式便能相互作用，直到它们之间产生一个固定的相位关系。也即形成锁模。在此基础上。去掉声光晶体，并用两个光栅作为腔镜，实现了全光纤法布里-珀罗(F-P)腔锁模光纤激光器。改变腔结构，分别采用光栅和光纤反射圈作为前后腔镜，同样观察到了锁模脉冲。经过观察发现，锁模脉冲的产生和掺Yb光纤的浓度、长度、抽运功率的大小有着密切的关系。这为锁模脉冲的产生提供了一种新的方法。     

Wavelength-switched optical pulse generation in a fiber ring laserwith a Fabry-Perot semiconductor modulator and a sampled fiber Bragggrating

A simple mode-locked fiber ring laser for generating wavelength-switched picosecond pulses was developed in which a laser diode played the role of both an intensity modulator and a tunable filter. A serially cascaded sampled fiber Bragg grating predefined the set of four allowable output wavelengths spaced 1.6 nm apart. Wavelength switching between the longest and shortest wavelengths required only a temperature change of the laser diode by 7.63°C     

Generation of wavelength-switched optical pulse from a fiber ringlaser with an F-P semiconductor modulator and a HiBi fiber loop mirror

A simple configuration to perform wavelength switching in an actively mode-locked fiber ring laser is demonstrated. A Fabry-Perot laser diode was used as a modulator and a HiBi fiber loop mirror was used as a periodic multichannel wavelength filter in the cavity. By setting the channel spacing of nm can be achieved by tuning the fiber loop mirror filter. In the wavelength-switched process, the modulation frequency was not required to be changed     

Alternate Multiwavelength Picosecond Pulse Generation by Use of an Unbalanced Mach–Zehnder Interferometer in a Mode-locked Fiber Ring Laser

A new laser architecture emitting alternate multiwavelength picosecond pulses at room temperature is proposed. The generation is based on a single active component, an unbalanced Mach-Zehnder interferometer, inserted in an actively mode-locked erbium-doped fiber ring laser to provide both intensity modulation and tunable filtering. Control of the emission is reached by inserting an additional modulator and a periodic filter in the cavity. We provide general insight into the operation of this type of laser by examining different regimes in simulations and experiments. Using this laser platform, we experimentally demonstrate the generation of three pulse trains at three different wavelengths at repetition rates of several gigahertz     

Direct generation of subpicosecond chirp-free pulses at 10 GHz froma nonpolarization maintaining actively mode-locked fiber ring laser

0.7-1.3 ps highly stable, transform-limited, sech²-shaped pulses at 10 GHz in the 1536-1569 nm wavelength region from a nonpolarization maintaining (PM), single intensity modulator, actively and harmonically mode-locked fiber ring laser have been directly generated. Little degradation of long-term stability of the laser operation was observed due to the non-PM nature of the laser cavity     

Tunable dual-wavelength actively mode-locked fiber laser with anF-P semiconductor modulator

A novel actively mode-locked fiber laser for generating dual-wavelength picosecond pulses is proposed by using a Fabry-Perot laser diode as the modulator in the ring cavity. A linear chirped fiber grating was used as a wavelength selector and produces temporal-spectral multiplexing of the pulses in the gain medium to reduce gain cross-saturation effects. About 2-GHz stable dual-wavelength pulses with a wavelength spacing of 0.92 nm at room temperature were experimentally demonstrated and the wavelengths could be tuned in a range of about 3 nm     

基于SOA的L波段多波长锁模光纤环形激光器

报道了一种基于半导体光放大器(SOA)的L波段多波长光纤环形激光器,采用自制的100GHz信道间隔的光纤Mach-Zehnder(M-Z)干涉仪作为梳状滤波器,电吸收调制器(EAM)实现主动锁模,在1593.6nm附近获得了11个波长的同步锁模脉冲序列,脉冲重复频率为10GHz,半高全宽约为24ps,不同波长间功率不平坦度小于1dB。激光器具有工作稳定、输出光谱较宽和不同波长间功率波动小的特性。