钛宝石飞秒激光器的锁模机理探讨

测量了X型折叠腔钛宝石飞秒激光器的发光动力学曲线，并运用传播圆 变换圆图解分析方法，系统地探讨了钛宝石飞秒激光器的自锁模机理和过程，提出了一种新的锁模机理——自脉动克尔透镜开关放大锁模. 关键词： 传播圆 变换圆 自脉动克尔透镜开关放大锁模 光学混沌     

用腔内半导体可饱和吸收镜钛宝石激光器中自锁模状态的实验研究

用可饱和吸收体镜(SESAM)的掺钛蓝宝石激光器能够稳定运转在三种不同的锁模状态,即可饱和吸收体被动锁模、孤子锁模加被动锁模和KLM锁模.分析了三种自锁模的机理和SESAM的作用.对SESAM实现KLM锁模的自启动机制进行了实验观察和讨论.从该激光器的KLM锁模状态,获得了小于18飞秒的锁模脉冲序列. 关键词： 半导体可饱和吸收镜 自锁模 钛宝石激光器     

钛宝石飞秒激光振荡器的稳定性改善

对钛宝石飞秒激光器脉冲序列的强度和时间的稳定性进行了分析.实验比较了钛宝石飞秒激光器底板有无水冷的条件下,输出锁模脉冲序列的稳定性以及中心波长和光谱宽度的变化.结果表明对钛宝石飞秒激光器底板施加水冷可改善锁模脉冲的稳定性. 关键词： 钛宝石激光器 稳定性 飞秒脉冲     

低阈值掺钛蓝宝石激光器实验研究

结合特殊的谐振腔设计和半导体可饱和吸收镜，建成了一台低阈值的自启动掺钛宝石激光器 . 分别用3％和12％的输出耦合镜，获得了阈值低至390mW和600mW的稳定锁模脉冲输出. 采 用12％输出耦合镜，在12W抽运时，输出平均功率为114mW，对应的典型脉宽为17fs，谱宽 为47nm. 相对于以往的低阈值克尔透镜锁模激光器，锁模工作的范围区域加宽，减小了操作 难度，提高了稳定性. 关键词： 低阈值 半导体可饱和吸收镜 克尔透镜锁模 掺钛蓝宝石激光器     

飞秒脉冲作用下光子晶体光纤超连续谱的产生

采用钛宝石超快fs激光器泵浦2m长光子晶体光纤产生超连续谱,重点研究了不同输入功率下350～959nm波长范围内光谱的演变过程,实验中产生的超连续光谱宽度超过550nm分析表明,内脉冲喇曼散射和孤子自频移在开始阶段对光谱长波方向上的展宽起主要作用,这些新的频率成分与随后光谱向短波方向的拓展有密切关系.     

连续自锁模钛宝石激光器

锁模的钛宝石激光器是近红外波段比较可靠的飞秒(fs)超短脉冲光源.用氩离子激光器,实现了连续钛宝石激光器自锁模运转,输出脉宽92fs、谱宽8.5nm、平均功率大于200mW、调谐范围750～850nm.实验中Ti:Al_2O_3自锁模激光器结构如图1所示,谐振腔采用了“Z”形折送四镜象散补偿腔,M_1和M_2为曲率半径150mm高反镜,M_3为耦合输出镜,透过率5%,M_4为平面高反端腔镜,总腔长为1.6m左右,非对称排布M_2M_3相似文献   

宽带自锁模钛宝石飞秒激光脉冲的实验研究

在线性Z形折叠腔的基础上,采用了一种能够消除输出耦合镜带宽限制的方法,用3mm的钛宝石短晶体和石英色散补偿棱镜得到了光谱带宽为121nm的自锁模钛宝石激光脉冲.在分析光脉冲自相关仪测量系统对测量影响的基础上,优化并基本消除了测量系统带来的影响,假设光脉冲形状为双曲正割型,得到了12fs的光脉冲,该光脉冲光谱半宽(FWHM)为87.6nm,中心波长为849.7nm,光脉冲平均输出功率为400mW,重复率为97MHz.     

自调Q自锁模固体激光器

利用被动锁模激光器的锁模原理,结合自锁模固体激光器中等效快可饱和吸收体的特性,讨论了控制运转状态的自锁模动力学方程和速率方程,给出了自调Q自锁模的条件,以及自调Q周期与激光器结构和运转参数的关系,所得结论与实验结果有很好的一致性。     

自锁模掺钛宝石激光器的泵浦研究

对自锁模掺钛宝石激光器的原理作了较详细的描述，指出克尔透镜效应是形成自锁模的主要原因，但是，只有将克尔透镜自聚焦、振荡光参数和泵浦光参数三者结合起来考虑，才能全面了解自锁模的形成过程，本文从速率方程出发，得出了激光介质增益与光束参数的相对变化曲线，并据此来优化自锁模钛宝石激光器的设计，最后，将计算结果与实验作了比较，两者符合得较好。     

利用SBR实现自启动锁模钛宝石飞秒激光脉冲的产生

利用国内生长的低损耗双量子阱结构的可饱和布拉格反射器在掺钛蓝宝石激光器中实现了可饱和吸收体被动锁模、孤子锁模和KLM锁模状态的自启动稳定运转.当抽运功率为4.5W时，用啁啾镜进行色散补偿，获得了18fs的KLM锁模脉冲，输出功率为150mW. 关键词： 可饱和布拉格反射器 啁啾镜 飞秒 钛宝石激光器     

Octave-spanning spectrum generation in Ti:sapphire oscillator

A Ti:sapphire oscillator emitting an octave-spanning spectrum that ranges from 460 to 1000 nm is demonstrated. To our knowledge, it is the first time that a supercontinuum as a whole measured after the output coupler extending beyond 500 nm in the blue end is generated from a femtosecond Ti:sapphire oscillator. In the Ti:sapphire oscillator operating in self-Q-switched and self-mode locked mode, two chirped mirrors and a prism pair were used for dispersion compensation. These experimental results would open a new option for the construction of simple continuum sources.     

采用飞秒光纤激光同步泵浦的自启动锁模钛宝石激光研究

针对常规连续激光泵浦钛宝石激光振荡器不能自启动锁模的缺点,采用倍频飞秒光纤激光同步泵浦,通过调节振荡器腔长与泵浦腔长匹配,实现了飞秒钛宝石激光的自启动锁模。实验中采用3.4 W的倍频掺镱光纤激光同步泵浦钛宝石激光振荡器,获得了平均功率大于130 mW、重复频率75 MHz、光谱宽度大于47 nm、脉冲宽度17 fs的锁模脉冲输出,不仅能够稳定可靠地实现自启动锁模,解决了常规钛宝石激光振荡器锁模启动的困难,而且还具有同步输出1040,800,520 nm三束飞秒激光的特点,为进一步开展飞秒激光相干合成以及光参量放大等研究提供了优势基础。     

Sub-10-fs pulse generation from a blue laser-diode-pumped Ti:sapphire oscillator

Pulses as short as 8.1 fs were generated from a blue laser-diode-pumped Kerr-lens mode-locked Ti:sapphire oscillator, with an average power of 27 m W and a repetition rate of 120.6 MHz. The full width at half-maximum exceeds 146 nm, benefitting from the dispersion management by a combination of a low-dispersion fused silica prism pair and a series of double-chirped mirrors. To the best of our knowledge, this is the first time to generate sub-10-fs pulses from a laser diode directly pumped Ti:sapphire oscillator.     

Self-stabilization of carrier-envelope offset phase by use of difference-frequency generation

Self-stabilized carrier-envelope offset phase is achieved by use of difference-frequency (DF) generation. The spectrum from a Ti:sapphire oscillator is broadened in a photonic crystal fiber, and a DF (900 nm) between the blue component (490 nm) and the infrared component (1080 nm) is generated. The beat signal between the fundamental and the DF signal is clearly observed. The wavelength of the DF signal can be tuned down to 780 nm, and hence the signal can be used for injection seeding of a Ti:sapphire oscillator.     

Monolithic 0–f Scheme-Based Frequency Comb Directly Driven by a High-Power Ti:Sapphire Oscillator

A monolithic O-f scheme-based femtosecond optical frequency comb directly driven by a high-power Ti:sapphire laser oscillator is demonstrated.The spectrum covering from 650 nm to 950 nm is generated from the Ti:sapphire oscillator with a repetition rate of 170 MHz.The average output power up to 630 mW is delivered under the pump power of 4.5 W.A 44-dB signal-to-noise ratio(SNR) of the carrier-envelope phase offset(CEO) beat note is achieved under the resolution of 100 kHz and is long-term stabilized to a reference source at 20 MHz.The integrated phase noise(IPN) in the range from 1 Hz to 1 MHz is calculated to be 138 mrad,corresponding to the timing jitter of 63 as at the central wavelength of 790 nm.     

Parametric amplification of few-cycle carrier-envelope phase-stable pulses at 2.1 microm

We demonstrate an optical parametric chirped-pulse amplifier producing infrared 20 fs (3-optical-cycle) pulses with a stable carrier-envelope phase. The amplifier is seeded with self-phase-stabilized pulses obtained by optical rectification of the output of an ultrabroadband Ti:sapphire oscillator. Energies of -80 microJ with a well-suppressed background of parametric superfluorescence and up to 400 microJ with a superfluorescence background are obtained from a two-stage parametric amplifier based on periodically poled LiNbO3 and LiTaO3 crystals. The parametric amplifier is pumped by an optically synchronized 1 kHz, 30 ps, 1053 nm Nd:YLF amplifier seeded by the same Ti:sapphire oscillator.     

Passive synchronization of two independent laser oscillators with a Fabry-Perot modulator

By optical modulation of the reflectivity of an intracavity nonlinear Fabry-Perot semiconductor mirror, the pulse train from a passively mode-locked picosecond Nd:YVO(4) laser oscillator is synchronized to an independent femtosecond-mode-locked Ti:sapphire laser. We obtain stable synchronized pulse trains at central wavelengths of 1064 and 850 nm, and the Ti:sapphire laser is still independently tunable over a large wavelength range. The tolerable cavity-length difference between the two laser oscillators exceeds 20mu;m .     

全固态kHz啁啾脉冲飞秒激光放大器

要建造大功率超强激光系统,必须将nJ量级的种子进行放大,以得到mJ量级以及更高能量的激光输出.为达到这个目的,必须使种子能量指数增加,再生腔放大器是实现这一目的的良好途径;同时,为了得到更稳定的激光输出,须采用高重复频率的泵浦源.为此,设计了一种kHz重复频率激光泵浦的再生放大器,使用15 mJ的527 nm的绿光泵浦,得到了约2.3 mJ的800 nm放大激光输出,同时,对其输出激光的光谱特性进行了测量,将带宽为40 nm的种子注入后,得到了光谱带宽约为30 nm激光输出.     

Generation of 7-fs laser pulse directly from a compact Ti:sapphire laser with chirped mirrors

A compact femtosecond Ti:sapphire laser resonator consisting of three chirped mirrors and one output coupler was designed. By accurately balancing the intra- cavity dispersions between Ti:sapphire crystal, air and chirped mirrors, we directly generated the laser pulse shorter than 7 fs at the average power of 340 mW with 3.1 W pump. The repetition rate of the laser oscillator is 173 MHz at the centre wavelength of 791 nm, and the ultrabroaden spectrum covers from 600 nm to 1000 nm. To the best of our knowledge, this is the simplest laser resonator capable of generating sub-10 fs laser pulse.