掺钕硅酸盐玻璃激光器中的自锁模现象

本文报道了在掺钕硅酸盐玻璃激光器中的自锁模现象,并对实验现象作了分析和讨论。     

自锁模激光器

概述了自锁模激光器的新成就（包括我们自已的工作）。在实验上，自锁模钛宝石激光器可以输出１３ｆｓ的短激光脉冲，这是直接从激光器中获得的最短脉冲；自锁模溴化亚铜激光器可以输出高稳定性的激光脉冲，从而彻底否定了自锁模没有实用价值的传统认识。在理论上，自克尔镜模型解释了自聚焦激光介质引起的锁模现象；增益凹陷模型解释了宽带激光介质自吸收起的锁模现象和窄带激光介质增益谱线分裂引起的锁模现象。最后，对它们的输出     

连续波锁模掺钕磷酸盐玻璃激光器光学谐振腔的分析

由于Nd:磷酸盐玻璃的热导率和破坏阀值都比较低,故连续波锈模钕磷酸盐玻璃激光器要求其谐振腔有特殊的设计.本文在谐振腔长度固定的限制下,分析了三元件式谐振腔的特性,并且讨论了连续波主动锁模Nd:磷酸盐玻璃激光器光学谐振腔的设计.我们讨论了在不同参量范围下谐振腔的稳定性范围和特性,并且阐明了有关的最佳参数的范围.给出了谐振腔最佳运转区参数的解析表达式.实验结果与理论预测符合得很好.这个解析式对设计三元件或多元件的任何端面泵浦和锁模谐振腔是很有用的.     

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   

掺钛蓝宝石自锁模环形激光器中的混沌现象

报道在掺钛蓝宝石自锁模环形激光器中出现的混沌现象.在一定的控制参数下,激光器可以相继运转在常规自锁模、准周期自锁模和混沌自锁模状态.实验结果验证了最近的理论预测. 关键词：     

克尔介质自锁模激光器的锁模启动及稳定性理论初探

描述了克尔介质自锁模激光器的锁模工作原理，建立了自锁模系统光强分辨率的概念，并指出了光强分辨率对自锁模系统的锁模启动和工作稳定性起着决定性的作用，通过合理控制克尔介质自锁模激光器的腔镜失谐角，可以提高系统的光强分辨率，从而使自锁模系统易于自锁模启动并提高其自锁模工作的稳定性。     

自锁模钛宝石激光器的研究

本文从实验上研究了Ti:Sapphire激光器中自锁模存在的腔长最大限度。当腔长大于2.7m时,未能观察到自锁模运转,但此时,用四棱镜系统进行色散补偿,得到了89fs的最短光脉冲。     

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。     

低功率泵浦Ti：Al2O3自锁模激光器

本文报道了低功率泵浦的Ｔｉ：Ａｌ２Ｏ３激光器实现了稳定的自锁模运转，锁模脉冲宽度为１８０ｆｓ。分析了激光器的结构及工作特性。     

CuBr自锁模激光器的实验研究

首次报道在纵向放电的CuBr激光器中,通过抑制高阶横模的振荡,同时得到高度稳定完全调制的绿光和黄光自锁模脉冲串,并在实验上研究了高阶横模,泵浦功率和谐振腔腔长对CuBr激光自锁模脉冲串及其纵模频谱的影响.     

Frequency pulling in an optically pumped submillimeter laser by Doppler induced dispersion

The dependence of the frequency of a CW optically pumped submillimeter laser on the frequency of its pump laser has been directly measured and shown to result largely from the dispersion produced by the two peaked gain spectrum resulting from pumping in the wings of a Doppler broadened absorption line.     

双模双光子激光的半经典理论

在本文中,拉姆(Lamb)的半径典激光理论被用来讨论双模双光子激光运转,将文献[7]的单模结果推广到两模频率相差甚大的双模双光子激光情况。     

Doppler velocimetry using self-mixing effect in a short Er–Yb-doped phosphate glass fiber laser

Accurate and highly sensitive speed measurements have been successfully demonstrated by the optical feedback velocimetry technique using the self-mixing modulation effect in a double-clad Er–Yb-doped fiber laser. The sensitivity to back-scattered light has been investigated regarding the Doppler frequency shift or the target distance, and it has been shown that the velocimeter is still sensitive to a target located at 20 m and for speeds as high as 13 m s^–1.     

Nd-doped phosphate glass microstructured optical fiber laser

We experimentally demonstrated a single-mode laser at 1056 nm with Nd-doped phosphate glass microstructured optical fiber (MOF), which was fabricated with conventional stack-and-draw method. The laser action was observed from a Fabry-Perot cavity formed by placing two dichroic mirrors of ∼100 and 85% reflectivity, to the two end facets of MOF. Pumped by CW laser diodes (LDs) at 808 nm, the MOF laser yielded a maximum output power of 8.5 mW and a slope efficiency of 2%.     

Self-mode-locking in a Q-switched Nd: doped silica fibre laser

Operating characteristics of a Q-switched Nd³⁺: doped single-mode silica fibre with a mechanical chopper as a Q-switching device are presented. Peak powers as high as 16 W with pulse duration of 146 ns are demonstrated. Self-mode-locking in Nd³⁺:doped fibre is also reported. An output power of 312 W with a centre pulse duration of 4 ns is observed.     

Ytterbium doped phosphate glass photonic crystal fiber laser

We demonstrate the 3% mol ytterbium doped phosphate glass air-clad photonic crystal fibre (PCF) laser of 43-cm length in single-mode operation. The fabrication and testing of the laser is introduced. The laser has the diameter of the core of 12 μm created in photonic microstructure and generates at wavelength of 1030 nm. Near 4-W output power and 14.6% slope efficiency against the launched pump power is demonstrated in preliminary characterization. The difference of refractive indices achieved in doped and undoped glass is Δn = 0.0004. We used the doped glass with the negative core-cladding Δn to assure the photonic crystal fibre way of single-mode propagation.     

Interference microscopy of femtosecond laser written waveguides in phosphate glass

By focusing fs-laser radiation in the volume of a transparent material the refractive index can be changed locally, leading to 3-dimensional waveguiding structures. Waveguides are written in phosphate glass (IOG from Schott) at a depth of 100 μm below the surface. The pulse energy and the scan velocity are varied. For the first time the optical path difference caused by the waveguides and therefore the refractive index distribution of the waveguides and their cross sections are determined using interference microscopy. The optical path difference measured in the written structures and their cross sections is analyzed by a phase-shift algorithm. Thus, the refractive index distribution both along a line perpendicular to the waveguide and in the plane of a cross section is determined. The results are visualized as 2-dimensional graphics. Several regions of opposite sign of the refractive index change are observed in the cross sections of waveguides generated by femtosecond laser pulses. The number and the size of these regions are increasing with increasing pulse energy and decreasing scan velocity.