Experimental and theoretical studies of complex pulse evolutions ina passively mode-locked ring dye laser

A detailed experimental and theoretical study has been made of the role of group velocity dispersion and self-phase modulation arising from time-dependent absorption saturation and the optical Kerr effect in a Rhodamine 110 CPM dye laser. Periodic pulse evolutions are observed, when both positive and negative frequency chirp are present, that are reminiscent of those governed by the nonlinear Schrodinger equation but that are, in fact, distinctly different. Similar results have been obtained with the standard Rhodamine 6G system, and it is believed that the theoretical model is generally applicable to any passively mode-locked femtosecond dye laser. An important consequence of these results is that they permit the absolute value of the group velocity dispersion in the laser cavity to be estimated     

A simple passively mode-locked CW dye laser

The operation of a simple passively mode-locked 5800-Å dye laser is reported. A single active medium, solution of rhodamine 6 G and diethyloxadicarbocyanine iodide (DODCI) in glycol flowing as an unconfined liquid film, is used for the simultaneous production of gain and non-linear absorption.     

Long pulse DCM dye laser

We describe a flashlamp pumped dye laser, incorporating both prepulse and simmer enhancement, which is capable of kW outputs for the 0.1 ms duration of the flashlamp pulse. The laser has been operated with the new dye DCM; we find that using oxygen or nitrogen gas in the dye solution greatly increases both laser amplitude and pulse duration.     

Ultrashort pulse generation from a passively mode-lockedTi:sapphire laser based system

The detailed characteristics of a passively mode-locked Ti:sapphire laser using saturable absorbers are described. This laser can stably generate nearly transform-limited sub-100-fs pulses around 780 nm. Combining this oscillator and a double-pass Ti:sapphire amplifier pumped by a CW Q-switched YAG laser (3 kHz) allows fiber-grating pulse compression down to 14 fs     

采用纵模匹配技术的短脉冲注入锁定染料激光器

本文报道了采用纵模匹配技术的短脉冲注入锁定染料激光器系统及实验结果.     

半导体泵浦被动调Q高重频Nd:YAG激光器

从被动调Q固体激光器的速率方程出发,分析给出了Cr4+:YAG被动Q开关Nd:YAG激光脉冲的峰值功率、脉冲能量、脉宽及重频等相关参量表达式.以此为基础,进行了光纤耦合输出的连续半导体激光纵向泵浦被动Q开关Nd:YAG激光器实验研究,采用不同参数Cr4+:YAG晶体作为被动Q开关,获得了不同参数的高重频脉冲激光输出.     

Injection locking of a passively mode-locked laser

We present and analyze a model of a passively mode-locked laser, which is subjected to injection of a coherent pulse train. The model, based on soliton perturbation theory, predicts the possibility of coherent injection locking, and gives analytical estimates for the locking ranges. The ability to simultaneously lock the timing and the phase of the output pulses of a mode-locked laser to an injected, coherent pulse train is shown. The interesting limiting case of phase locking the mode-locked laser to a constant amplitude external injection, is addressed with implications for future coherent soliton communication systems     

碰撞锁模染料激光器中激光脉冲的啁啾特性及其色散补偿

从实验上研究了碰撞锁模染料激光器中激光脉冲的啁啾性质.分析了采用两块棱镜组成的棱镜对进行内腔补偿时,棱镜对的色散对输出激光脉冲的宽度、稳定性及光谱特性的影响.     

Near-infrared dye laser pumped by a carbazine-122 dye laser

Efficient generation of a high-power near-infrared dye laser has been achieved by pumping longitudinally with a 5321-Å pumped carbazine-122 dye laser at 7000 Å. A peak power as high as 3.5 MW at 8630 Å and peak powers in excess of 0.5 MW from 7680 to 9170 Å have been obtained.     

Pulse shaping in passively mode-locked ring dye lasers

The concept of "pulse shortening velocity" is introduced as a simplified measure of pulse width performance in passively mode-locked ring dye lasers. Pulse shapes have been computed for a variety of operating conditions. The influence of coherent coupling in colliding pulse systems is found to be essentially equivalent to that of an increased saturable absorber cross section.     

Picosecond pulse generation from passively modelocked vertical cavity diode laser at up to 15 GHz pulse repetition rate

The generation of ultrashort pulses (/spl sim/15 ps) from a passively modelocked InGaAs multiple quantum well (MQW) vertical cavity surface emitting diode laser is reported at a repetition rate up to 15 GHz, utilising a cavity configuration that incorporates a reverse-biased quantum well device as a fast saturable absorber. Pulsing at up to 20 GHz rate has been observed on a continuous-wave background.     

Optimization of passively mode-locked giant pulse lasers

Simple functions that characterize the performance of a passively mode-locked giant pulse laser have been identified for the first time. These provide essential information for optimizing this class of laser system. The analytical results are supported by a computer model which includes the noise statistics in a realistic way, and allows quantitative simulations of real mode-locked systems to be carried out.     

被动锁模光纤环形孤子激光器的自起动分析

本文从激光器工作的两种平衡态出发 ,具体分析了被动锁模光纤环形孤子激光器的自起动特性与其结构参数的关系 ,并用分裂步长法对激光器的自起动特性做了数值模拟 ,获得了稳定的孤子脉冲序列。     

Noise in pulsed injection locking of a passively modelocked laser

In this paper, noise effects related to pulsed injection locking of a passively modelocked laser (PML) are analyzed. A set of nonlinear equations, derived from a soliton perturbation method, is used to describe the modelocked laser pulse evolution, under injection locking. The equations are linearized, and the stability of the injection locked solution is studied. Subsequently, the linear equations are employed to describe the coupling of both the injected signal noise and the internal noise, to the locked pulses. Noise reduction due to the injection process is demonstrated, with important implications for all optical signal regeneration and synchronization     

An investigation into femtosecond pulse formation in acontinuously-pumped passively-mode-locked CPM ring dye laser

A detailed experimental investigation of the formation of ultrashort pulses in a CW-pumped passively mode-locked CPM dye laser is described. It is found that it takes ~10⁴ round trips for the circulating energy in the cavity to reach the level at which the passive mode-locking process is initiated, and a subsequent ~10³ round trips for the ultrashort pulse evolution to reach a steady state. Sequences of autocorrelation profiles and spectra are presented showing the dynamic pulse evolution, and the influence of intracavity group velocity dispersion on pulse formation is examined     

Picosecond pulse generation with 1.5 /spl mu/m passively modelocked surface-emitting semiconductor laser

The authors report the first demonstration of an optically pumped passively modelocked surface-emitting semiconductor laser operating in the 1.5 /spl mu/m region. The modelocked laser emits pulses of 6.5 ps full width at half maximum duration with an average power of 13.5 mW at a fundamental repetition rate of 1.342 GHz. The peak power was 1.6 W.     

脏外染料被动压缩准分子激光的输出脉冲特性研究

用紫外染料PTP、BPBD、t-B_uPBD等对XeC1准分子激光施行腔外被动压缩,获得了压缩比为3的XeC1激光脉冲透射输出和压缩比大于8的染料辐射输出。提出“光子传输速率方程”来描述被动压缩现象,计算机模拟计算结果较好地解释了准分子激光压缩及染料辐射的实验结果。     

Nanosecond pulse generation in a passively Q-switched Yb-doped fiber laser by Cr/sup 4+/:YAG saturable absorber

We explored efficient nanosecond pulse generation in a passively Q-switched cladding-pumped Yb-doped fiber laser by use of an external-cavity configuration containing a Cr/sup 4+/:YAG saturable absorber crystal. By exploiting passive Q-switched regime and stimulated Brillouin scattering, pulses of durations as short as 2.7 ns, corresponding to a peak power of /spl sim/9 kW, have been achieved. The laser was tunable over 70 nm and green output power generation was obtained by external frequency doubling in a KTP crystal.     

Low-noise operation modes of a passively mode-locked fiber laser

Optimum low-noise operation modes of a passively mode-locked fiber laser are described and characterized. The laser produces 60 fs bandwidth limited pulses with root mean square amplitude fluctuations of 0.4% in a frequency-band from 30 Hz to 100 kHz. It is shown that low-noise operation up to 5 dB below the amplitude noise of the pump laser is possible with overall negative cavity group-velocity dispersion and a large difference between the intracavity loss under free-running and mode-locked laser operation. Additional frequency stabilization reduces the timing jitter to 4 fs in a frequency band from 1 kHz to 100 kHz and 110 fs in the 30 Hz to 100 kHz band