共查询到20条相似文献,搜索用时 331 毫秒
1.
We report the generation of 207-fs pulses with 1.2mW average power
at 1036nm directly from a passively mode-locked Yb-doped fibre
laser with a nonlinear optical loop mirror for mode-locking and pairs
of diffraction gratings for intracavity dispersion compensation.
These results imply a 4-fold reduction in pulse duration over
previously reported figure-of-eight cavity passively mode-locked
Yb-doped fibre lasers. Stable pulse trains are produced at the
fundamental repetition rate of the resonator, 24.0MHz. On the other
hand, this laser offers a cleaner spectrum and greater stability and
is completely self-starting. 相似文献
2.
Experimental Study of a Pulsed Ytterbium-Doped Fibre Laser with Fast and Slow Saturable Absorbers in a Linear Cavity 下载免费PDF全文
We present a linear-cavity stretched-pulse fibre laser and by semiconductor saturable-absorber mirrors. A with mode locking by a nonlinear polarization rotation Q-switched mode-locking cw train and a mode-locking pulse train are obtained in the experiment. We investigate the effects of the equivalent fast saturable absorber and the slow saturable absorbers in experiment. It is found that neither the nonlinear polarization evolution effect nor a semiconductor saturable absorber mirror is enough to produce the stable cw mode-locking pulses in this experiment. A nonlinear polarization evolution effect controls the cavity loss to literally carve the pulses; semiconductor saturable absorber mirrors provide the self-restarting and maintain the stability of the modelocking operation. 相似文献
3.
A. G. Bulushev E. M. Dianov A. V. Kuznetsov O. G. Okhotnikov 《Optical and Quantum Electronics》1990,22(6):491-500
This paper discusses the use of single-mode fibre ring interferometers for injection laser line narrowing and for enhancement of optical emission power. The efficient launching into fibre ring interferometers of multi-frequency external cavity injection laser emission, in both the c.w. and mode-locking regime, has been achieved. Matching the optical lengths of the external cavity and fibre interferometer allowed the measurement of mode width of such a laser. A method is proposed for shaping optical pulses in fibre ring interferometers from constant intensity frequency modulated emission. The mode-locking regime of all-fibre external cavity injection lasers has been achieved. 相似文献
4.
We demonstrate the experimental observation of different operation states in erbium-doped fiber ring laser with normal cavity
dispersion. The Q-switching, Q-switching mode-locking (QML), continuous wave mode-locking (CML), harmonic mode-locking (HML),
double-pulse and multiple-pulse operation states can be manipulated by only adjusting the polarization controller with the
same pump power. The output spectral bandwidth and pulse width of operation states are measured. The central wavelength dynamics
of different operation states achieved by adjusting the polarization controller are also observed and analyzed. It is shown
that pulse width, polarization, chirp and stability of different operation states are diverse by using nonlinear polarization
rotation technique. 相似文献
5.
6.
We demonstrate a harmonic mode-locked ytterbium-doped fibre ring laser, which consists of a polarization-sensitive isolator, two polarization controllers, two 976nm laser diodes as the pump source and a two-segment ytterbium-doped fibre. Utilizing an additive pulse mode-locked technique based on nonlinear polarization evolution, the ytterbium-doped fibre laser can operate in mode-locked state by adjusting the position of polarization controllers. The cavity fundamental repetition rate is 23.78 MHz. We also observe the second- and third-harmonic mode locking in the normal dispersion region, and their repetition rates are 47.66 MHz and 71.56 MHz, respectively. Over-driving of the saturable absorber in the harmonic mode-locking pulse is analysed and discussed in detail. 相似文献
7.
Passive harmonic mode-locking of dissipative solitons is demonstrated in all-normal dispersion Yb-doped fibre lasers.A difference equation model of the mode-locked fibre lasers is adopted to simulate the intra-cavity nonlinear dynamics.Hysteresis phenomena around the mode-locking threshold,and the effect of introducing linear phase bias are discussed.The passive harmonic mode-locking as one kind of multipulsing operations is revealed.Moreover,the simulation shows the bistability between multipulsing and single-pulse or period multiplication. 相似文献
8.
Jaekwon Ko Hwanseong Jeong Sun Young Choi Fabian Rotermund Dong-Il Yeom Byoung Yoon Kim 《Current Applied Physics》2017,17(1):37-40
We demonstrated four different laser operational states in the same passive fiber ring laser cavity by controlling solely the polarization state in a saturable absorber. The demonstrated laser operational states were continuous wave, mode-locking, Q-switching, and Q-switched mode-locking. The saturable absorber was fabricated by spin-coating a single-walled carbon nanotubes (SWCNT)/polymer composite on a side polished fiber providing enhanced nonlinear interaction with the SWCNT. The wide tuning range of the saturable absorber allows the simple means to generate different forms of laser output from a single laser cavity. 相似文献
9.
10.
A detailed numerical model analysis of the synchronously mode-locked CW dye laser is presented. In the analysis, good mode-locking is found mainly for negative cavity detuning. The calculated cavity length detunig effects are compared with the results of experiments performed on the Oxazine-1 dye laser. The agreement between theory and experiment is satisfactory. The experimental good mode-locking regime is predicted correctly by this analysis. The present calculations are also compared with the hitherto reported qualitative model analyses with a gaussian dye pulse approximation. The validity of these model analyses is examined. 相似文献
11.
Passive harmonic mode-locking of dissipative solitons is demonstrated in all-normal dispersion Yb-doped fibre lasers. A difference equation model of the mode-locked fibre lasers is adopted to simulate the intra-cavity nonlinear dynamics. Hysteresis phenomena around the mode-locking threshold, and the effect of introducing linear phase bias are discussed. The passive harmonic mode-locking as one kind of multipulsing operations is revealed. Moreover, the simulation shows the bistability between multipulsing and single-pulse or period multiplication. 相似文献
12.
建立理论模型,讨论了非线性偏振旋转全光纤锁模激光器的锁模过程、谐波过程以及导致激光器锁模运行难以稳定的影响因素.讨论了采用啁啾脉冲光谱滤波产生脉冲自振幅调制、增加激光器锁模稳定性和自启动能力的机理以及非线性偏振旋转与啁啾脉冲光谱滤波相结合实现锁模的物理过程和脉冲演化过程.研制出全光纤结构的超短脉冲掺Yb~(3+)光纤环形激光器,采用非线性偏振旋转和啁啾脉冲光谱滤波相结合的锁模技术,实现了激光器锁模的开机自启动和高稳定运行.对激光器进行了长期运行稳定性、锁模开机自启动能力、锁模输出参数可重复性监测.锁模脉冲中心波长1052.9 nm,谱宽9.1 nm,脉冲能量4.25 nJ,脉冲宽度17.8 ps.运行期间,各参数波动均小于0.3%.开机自启动能力和可重复性测试显示,激光器可实现一键自启动,启动后各参数可重复精度在0.55%以内. 相似文献
13.
We report a highly efficient and high power self-starting femtosecond Cr:forsterite laser pumped by a 1064-nm Yb doped fibre laser. Five chirped mirrors are used to compensate for the intra-cavity group-delay dispersion, and the mode-locking is initiated by a semiconductor saturable absorber mirror (SESAM). Under pump power of 7.9 W, stable femtosecond laser pulses with average power of 760mW are obtained, yielding a pump power slope efficiency of 12.3%. The measured pulse duration and spectral bandwidth (FWHM) are 46 fs and 45 nm; the repetition rate is 82 MHz. 相似文献
14.
We demonstrate a wavelength-tunable, passively mode-locked erbium-doped fiber laser based on graphene and chirped fiber Bragg grating. The saturable absorber used to enable passive mode-locking in the fiber laser is a section of microfiber covered by graphene film, which allows light-graphene interaction via the evanescent field of the microfiber. The wavelength of the laser can be continuously tuned by adjusting the chirped fiber Bragg grating, while maintaining mode-locking stability. Such a system has high potential in tuning the mode-locked laser pulses across a wide wavelength range. 相似文献
15.
16.
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12W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 相似文献
17.
研究了偏斜光线抽运下的回音壁模式光纤激光辐射特性.实验发现,在抽运光以偏斜光线方式沿光纤的近轴向抽运时,回音壁模式的光纤激光辐射中,既存在光电矢量和光纤径向垂直的横电波(TE),也存在光电矢量和光纤径向平行的横磁波(TM);随增益包层染料溶液折射率的增加,径向模式数和角模式数相同的TE波和TM波之间的波长差单调减小,回音壁模式激光辐射的中心波长向短波方向移动,辐射的波长范围变窄.用回音壁模式激光的辐射理论结合激光染料的四能级模型,满意地解释了实验结果. 相似文献
18.
We report the first double and colliding pulse mode-locking (DCPM) of an Ar+ and a dye laser in a ring cavity. An analytic solution for the stability of this ring cavity is presented, together with the experimental results on the DCPM laser. 相似文献
19.
Vasilios Zarikas 《Optics Communications》2006,263(2):239-248
In this paper, we present a self-consistent model of an optically mode-locked semiconductor fiber ring laser. The fiber laser uses a semiconductor optical amplifier (SOA) as the gain medium, while mode-locking is achieved by its gain modulation, via an external optical pulsed signal. We solved the model analytically developing a novel technique, where we have assumed double saturation of the SOA by both the mode-locked and the externally introduced pulsed signal. The study revealed the locus of the laser parameters to achieve mode-locking. In particular, it was found that SOA gain and energy of the externally introduced signal are two critical parameters that must simultaneously set properly for exact mode-locking. Another outcome of our analysis is that the study of the chirp parameter should be carried out keeping the nonlinear terms of the SOA gain. We have also investigated a slightly detuning regime of operation that revealed a fast change of the mode-locking process. 相似文献
20.
We report on the experimental observation of soliton pulses in an
erbium doped fibre ring laser. The passive mode-locking is achieved
using the nonlinear polarization rotation technique. By adjusting the
pump power and the intracavity polarization controllers, a normal
soliton, a stable 8th harmonic mode-locked pulse and a noise-like
pulse have been observed in our laser. The experimental results
revealed that the noise-like pulse is not suitable for the optical
telecommunication, and in order to obtain the stable harmonic
mode-locked soliton, a strong unstable CW laser field is necessary to
mediate global soliton interaction. The formation mechanism of the
harmonic mode-locked pulse has also been analysed. 相似文献