共查询到20条相似文献,搜索用时 0 毫秒
1.
We report experimental and numerical results on the dynamics of gain-guided solitons in a passively mode-locked erbium-doped fiber laser made of purely normal dispersion fibers. We show that formation of the soliton in the laser is a result of mutual interaction and balance among the cavity transmission, fiber Kerr nonlinearity, gain saturation, and filtering over one cavity round trip. 相似文献
2.
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
3.
High-power all-normal-dispersion femtosecond pulse generation from a Yb-doped large-mode-area microstructure fiber laser 总被引:3,自引:0,他引:3
We report on an all-normal-dispersion mode-locked fiber laser based on a large-mode-area Yb-doped microstructure fiber and using a high nonlinear modulation depth semiconductor saturable absorber mirror. The laser delivers 3.3 W of average output power with positively chirped 5.5 ps pulses at a center wavelength of 1033 nm. The pulse repetition rate is 46.4 MHz, which results in an energy per pulse of 71 nJ. These pulses are extracavity dechirped down to 516 fs by using bulk gratings. The average power of the dechirped pulses is 2.3 W, which corresponds to a peak power of more than 96 kW. 相似文献
4.
We report a 1030 nm-wavelength Yb:fiber laser that produces the shortest/direct output pulse duration (502 fs) among all-normal-dispersion fiber lasers at the highest repetition rate (605 MHz) among the passively fundamentally mode-locked fiber lasers. The laser also exhibits an optical efficiency of 70% at CW and 65% at mode-locking modes. 相似文献
5.
Pottiez O. Ibarra-Escamilla B. Kuzin E. A. Grajales-Couti?o R. Carrillo-Delgado C.-M. 《Laser Physics》2010,20(3):709-715
We propose and study numerically an all-normal-dispersion Ytterbium-doped figure-eight fiber laser scheme for generation of
high-energy pulses. The monotonous pulse stretching that takes place in the fiber under the combined actions of normal dispersion
and nonlinear Kerr effect is compensated by the amplitude modulation effect of a bandpass filter inserted in the ring section
of the laser. The Nonlinear Optical Loop Mirror (NOLM) also contributes to shorten the pulses. An output coupler with a large
output coupling ratio is inserted at the amplifier output in order to extract the maximal energy from the laser. A short segment
of Ytterbium-doped fiber compensates for the losses. Stable single-pulse operation is predicted over a wide range of values
of the laser parameters. If the laser parameters (ring and NOLM length, dispersion, filter bandwidth, output coupling ratio)
are optimized, pulses with several tens of nanojoules energy are readily obtained, with picosecond duration and a large positive
chirp which is linear near the peak. If small-signal gain is large enough, the use of very large output coupling ratios opens
the way to pulse energies close to 100 nJ and, after dechirping outside the laser, to durations of ˜50 fs and peak powers
of 1 MW. 相似文献
6.
We present an environmentally-stable picosecond Yb-doped fiber laser by employing an achromatic quarter-wave-plate (AQWP)
as a pulse stabilizer in the all-normal-dispersion and polarization-maintaining linear laser cavity. It is shown that the
AQWP plays a critical role to control both the polarization state and spectral filtering of the proposed mode-locked laser.
The demonstrated laser generates 2-ps-long pulses with pulse energies of 1 nJ at a repetition rate of 117 MHz and parabolic
spectral width of 26 nm. The fundamental RF carrier frequency exhibits Allan deviation of 3.8 × 10−8 at 1-s averaging time and phase noise of −95 dBc/Hz at 10-Hz offset frequency. 相似文献
7.
Weiqing Gao Meisong Liao Hiroyasu Kawashima Takenobu Suzuki Yasutake Ohishi 《Optics Communications》2012,285(18):3809-3815
We demonstrate different operation states which can be switched by the polarization control in an erbium-doped fiber laser cavity with normal dispersion, including passive single-pulse and multiple-pulse mode-locking, coherent pulse pattern, and passive Q-switching. The mode-locked single pulse has a smooth and broad rectangular-shaped spectrum. With increasing pump power, multiple pulses appear and finally six pulses are observed, where the pulses have no interaction with each other. Keeping the pump power at 407 mW and adjusting the polarization state, we observe the coherent pulse pattern with the pulse numbers from 2 to 5. It is the first time five coherent pulses in the 1.55 μm normal dispersion cavity have been observed, to our knowledge. The mode-locked spectra are highly modulated and the largest pulse separation of 31.9 ps is observed for the two-pulse case. When the pump power exceeds 180 mW, the mode-locked operation can be switched to the passively Q-switched operation by controlling the polarization state. The repetition rate and pulse width can be changed by pump power variation, and the spectrum is tunable in the range of 8.45 nm. 相似文献
8.
9.
A compact and stable all-normal-dispersion mode-locked ring fiber laser with the repetition rate of 312 MHz is obtained with a wavelength-division multiplexing isolator. The compressed pulse is nearly transform-limited and the pulse width is 118 fs. It exhibits an optical efficiency of 50% and the maximum output power is about 205 m W with a 410 m W pump. 相似文献
10.
11.
A multiwavelength actively mode-locked fiber ring laser that utilises a single semiconductor optical amplifier as both a gain and mode-locking element is presented. It is verified experimentally that the number of mode-locked wavelengths may be maximised by compensating for the anomalous intra-cavity dispersion. This is achieved through the inclusion of an appropriate length of normal dispersion fiber in the laser cavity. Using this technique, the number of wavelengths simultaneously mode-locked at 10 GHz was increased from 2 to 5. 相似文献
12.
A compact Er:fiber ring laser operated at a fundamental repetition rate of 325 MHz is reported.Two gain fibers with opposite dispersion are employed to shorten the fiber laser cavity for high repetition rate and soliton-like pulse generation without losing gain and compactness.The spectral bandwidth of the output pulse is 24 nm and the direct pulse duration is 123 fs without extra-cavity compression,which are values near the transform-limited range. 相似文献
13.
采用非线性偏振旋转锁模,构建了一种全正色散掺Yb3+光纤环形激光器.在该激光腔内采用了10 nm带宽的光纤滤波器提供附加的自振幅调制.通过改变滤波器在腔内的位置,实验证明了滤波器位置对高啁啾脉冲的整形过程起到重要的作用.在320 mW的抽运功率下,最终获得平均功率为922 mW,脉冲重复频率为266 MHz,脉冲宽度为62 ps的稳定脉冲输出,单脉冲能量达35 nJ的优化结果.通过数值模拟与实验结果的验证表明,两者相符很好.
关键词:
锁模光纤激光器
全正色散
滤波效应
高啁啾脉冲 相似文献
14.
We have found theoretically that the intracavity dispersion of a laser is independent of the pumping power and wavelength and that the resonant group-velocity dispersion vanishes. We have experimentally observed that the intracavity dispersion of an erbium-doped fiber laser was independent of the pumping power and wavelength within the measuring error, which agrees well with our theoretical predictions. 相似文献
15.
Hui-Yi Wang Wen-Cheng Xu Ai-Ping Luo Jiang-Li Dong Wen-Jun Cao Lu-Yan Wang 《Optics Communications》2012,285(7):1905-1907
We report on the controllable generation of the dissipative soliton and the Q-switched pulse in a normal dispersion fiber ring laser. The hybrid saturable absorber is used to obtain the dissipative soliton or the Q-switched pulse by slightly adjusting the polarization controller. Based on the experimental results and theoretical analysis, the controllable dissipative soliton and Q-switched pulse emission can be induced by the cavity loss tuning mechanism of the fiber laser. 相似文献
16.
Fiber optical parametric oscillator based on photonic crystal fiber pumped with all-normal-dispersion mode-locked Yb:fiber laser 下载免费PDF全文
We demonstrate a cost effective, linearly tunable fiber optical parametric oscillator based on a home-made photonic crystal fiber pumped with a mode-locked ytterbium-doped fiber laser, providing linely tuning ranges from 1018 nm to 1038 nm for the idler wavelength and from 1097 nm to 1117 nm for the signal wavelength by tuning the pump wavelength and the cavity length. In order to obtain the desired fiber with a zero dispersion wavelength around 1060 rim, eight sam- ples of photonic crystal fibers with gradually changed structural parameters are fabricated for the reason that it is difficult to accurately customize the structural dimensions during fabrication. We verify the usability of the fabricated fiber experimen- tally via optical parametric generation and conclude a successful procedure of design, fabirication, and verification. A seed source of home-made all-normal-dispersion mode-locked ytterbium-doped fiber laser with 38.57 ps pulsewidth around the 1064 nm wavelength is used to pump the fiber optical parametric oscillator. The wide picosecond pulse pump laser enables a larger walk-off tolerance between the pump light and the oscillating light as well as a longer photonic crystal fiber of 20 m superior to the femtosecond pulse lasers, resulting in a larger parametric amplification and a lower threshold pump power of 15.8 dBm of the fiber optical parametric oscillator. 相似文献
17.
Yuepeng Feng Yikun Lin 《International Journal of Infrared and Millimeter Waves》1992,13(12):1959-1966
The miniaturization of OPFIRL plays an important role in application of this new wavelength range of electromagnetic wave, especially in that of spaceflight where efficiency and miniature are emphasized.[1][8] So it is important to optimize the operating parameters of OPFIRL. This article will start with density matrix equations, then calculate the FIR output power density under different operating conditions by means of iteration calculation. And then parameters of the laser will be changed in order to study it's spectral characteristic of the FIR laser. We found that, working under the optimum operating gas pressure, FIF output power varies with the output coupling of the cavity OPFIRL. There is an optimum value of reflection coefficient Ro of the output window which makes the output FIR power denity and spectral characteristic of miniature OPFIRL optimum. 相似文献
18.
《中国光学快报(英文版)》2019,(12)
Experimental generation of stable mode-locked pulses and cylindrical vector beams(CVBs), from an all fewmode fiber(FMF) ring laser is first reported, to the best of our knowledge. In this laser, a section of few-mode erbium-doped fiber(FM-EDF) is used as the gain medium. The FM-EDF is pumped by 976 nm laser with LP11 mode, which is simultaneously converted and multiplexed through a homemade hybrid device, i.e., wavelength division multiplexing-mode selection coupler(WDM-MSC). All the components in our experiment are connected using FMF. The resulted CVB pulses have a spectral width of 0.33 nm with a repetition rate of 30.58 MHz under the pump power of 340 m W. Moreover, both azimuthally and radially polarized CVBs were achieved with a high purity of 95%. This mode-locked CVB fiber laser with an all FMF configuration opens the way to manipulate the transverse mode in mode-locked fiber lasers. 相似文献
19.
It is well known that saturating gain media can give rise to superluminal pulse propagation velocity. In most mode-locked
lasers the effect is unmeasurably small and has not yet been directly demonstrated. We present experiments on the initial
transient of an erbium fiber laser that show a dynamic shift in the propagation velocity to a value larger than the medium’s
linear group velocity as the pulse builds up.
Received: 14 December 1998 / Revised version: 21 May 1999 / Published online: 25 August 1999 相似文献
20.
We report on monotonically positively chirped pulse operation of a hybridly mode-locked thulium fiber laser. Dispersion management was realized with a small-core, high-NA fiber providing normal dispersion in the 2 μm wavelength region. The laser delivered pulses with 0.7 nJ energy at the 1927 nm center wavelength and sub-500-fs pulse duration after compression. 相似文献