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排序方式: 共有225条查询结果,搜索用时 8 毫秒
31.
Xiao-Qin Liu 《中国物理 B》2022,31(11):114205-114205
Yb3+:CaF2-YF3 transparent ceramics with excellent optical quality was successfully fabricated by hot-pressed method. Pulsed laser properties of this ceramics were investigated for the first time. Laser diode (LD) was applied as the pump source to generate a dual-wavelength mode-locked (ML) laser. The maximum average output power was 310 mW, which represents the highest output power of ultrafast calcium fluoride ceramic laser. The spectrum separated at 1048.9 nm and 1049.7 nm with a total pulse duration of 8.9 ps. The interval period between the beating signals was about 4.3 ps, corresponding to a 0.23 THz beat pulse repetition rate. These results demonstrate its potential in producing dual-wavelength ultrashort pulses. These Yb3+:CaF2-YF3 ceramics with low-cost and short-preparation period are ideal candidate materials for ultrafast lasers. 相似文献
32.
The mechanism of femtosecond optical pulse generation in a self-starting Er3+-doped fiber ring soliton laser and experimental research results are discussed. Using the nonlinear polarization rotation
effect of the fiber for sat-urable absorbers (and then self-amplitude modulation) which acts as the mode locking mechanism
in an Er3+-doped fiber ring cavity laser, stable self-starting mode locking pulses have been generated. The shortest output pulse is
269 fs, with the central wavelength of 1,531 pm at the repetition rate of 21.37 MHz. The average output powen of the two terminators
of the laser are 0.25 mW and 0.08 mW respectively. The threshold pump power which sustains the mode locking is 15 mW. Under
high pump power, the laser works in a high order harmonic mode locking state. The mode locking pulse durations vs different
cavity lengths are also studied.
Project supported by Major Project of Chines: Academy of Sciences (No. KJ952-J1-705). 相似文献
33.
Closed form solutions for a simultaneously AM and high-harmonic FM mode locked laser system is presented. Analytical expressions
for the pulsewidth and pulsewidth-bandwidth products are derived in terms of the system parameters. The analysis predicts
production of 17 ps duration pulses in a Nd:YAG laser mode locked with AM and FM modulators driven at 80 MHz and 1.76 GHz
for 1 W modulator input power. The predicted values of the pulsewidth-bandwidth product lie between the values corresponding
to the pure AM and FM mode locking values. 相似文献
34.
Jiahao Chen Yingtian Xu Yang Liu Heng Liu He Zhang Liang Jin Linlin Shi Yunping Lan Yonggang Zou Jie Fan 《Advanced functional materials》2024,34(12):2313027
2D conjugated metal-organic frameworks (MOFs) with high in-plane-π-conjugation are attracting significant attention in various fields owing to their outstanding electrical transport property, substantial specific surface areas, and tunable structures. However, their potential in ultrafast photonics has not been extensively explored. Herein, 2D conjugated Ni3(HITP)2 metal-organic framework (MOF) and graphene (GR) π–π stacked vertical heterostructures (NG-VHS) are synthesized using an ultrasound-assisted method. Based on theoretical simulations and characterization analyses, the results suggest that the fast interface charge transfer and the extension of the π-conjugated electron cloud will significantly enhance the electrical conductivity and the nonlinear optical properties, which is attributed to the π–π stacking interactions between Ni3(HITP)2 and GR. The charge transfer rate of NG-VHS is given by 6.9 × 1011 s−1. Noticeably, NG-VHS can serve as an excellent saturable absorber (SA) that can achieve fundamental mode-locking with a pulse width of 451 fs, harmonic mode-locking with repetition frequencies up to 1.205 GHz, and tunable dual-wavelength mode-locking. These results indicate the potential of NG-VHS as a promising nonlinear optical material for ultrafast optical applications and a new platform for the design of advanced optoelectronic devices based on 2D conjugated MOFs. 相似文献
35.
半导体可饱和吸收镜被动锁模侧面抽运Nd:YAG激光器研究 总被引:2,自引:0,他引:2
利用半导体可饱和吸收镜(SESAM)锁模技术实现的超快脉冲激光器具有结构简单紧凑、脉冲序列稳定等优势,在许多领域有着重要用途,自问世以来受到国内外的广泛关注.分析了SESAM被动锁模侧面抽运固体激光器的具体要求,进行了不同条件下的SESAM被动锁模侧面抽运Nd:YAG激光器实验.获得了最高平均功率9.5 W,脉冲重复频率71 MHz,单脉冲能量约141 nJ的皮秒激光脉冲.对SESAM被动锁模侧面抽运Nd:YAG激光器进行了实验和理论分析,对实现高功率连续超短脉冲激光器进行了探讨. 相似文献
36.
Andrey A. Ionin Yuriy M. Klimachev Andrey A. Kotkov Andrey Yu. Kozlov Leonid V. Seleznev Dmitriy V. Sinitsyn 《Optics Communications》2009,282(2):294-299
Actively mode-locked electron-beam-sustained-discharge CO laser producing a train of ∼5-15 ns (FWHM) spikes following with repetition rate 10 MHz for both single-line and multiline mode of operation in the mid-IR range of ∼5 μm was experimentally studied. Total laser pulse duration was ∼0.5 ms for both mode-locked and free-running laser. Specific output energy in multiline CO laser mode of operation was up to 20 Jl−1 Amagat−1 and the laser efficiency up to 3.5%. The active mode-locking was achieved for single-line CO laser mode of operation in spectral range 5.2-5.3 μm. This sort of radiation can be used for pumping an optical parametric amplifier for optical stochastic cooling in relativistic heavy ion collider, for laser ablation, and for studying vibrational and rotational relaxation of CO and NO molecules. 相似文献
37.
构建了可自启动的双波长运转掺铒光纤锁模激光器.通过优化增益光纤长度,利用掺铒光纤在1530nm附近的再吸收效应调节激光器的增益谱,使激光器在1530nm和1560nm附近具有相同的增益强度.实验中采用31cm掺铒光纤作为增益光纤,以透射式半导体可饱和吸收体作为锁模器件,实现了自启动双波长锁模运转.激光器锁模输出重复频率为58.01MHz,信噪比为58.2dB,最高输出功率为4.8mW.锁模输出的光谱在1532.4nm和1552.3nm处具有两个强度接近的谱峰,谱峰间距约为20nm.该激光器无需手动调节即可实现双波长运转,更便于实际使用. 相似文献
38.
基于单壁碳纳米管可饱和吸收体的被动锁模光纤激光器研究 总被引:3,自引:1,他引:2
基于单壁碳纳米管(SWCNTs)作为光学可饱和吸收体(SA)的恢复时间快(<1ps)、饱和光强低、锁模自启动、工作光谱范围宽且制备方法简单、成本低、化学稳定性好、易与光纤兼容等优点,利用SWCNTs-SA实现了稳定脉冲序列输出的实验结果。利用聚甲基丙烯酸甲酯(PMMA)易成膜且机械性能良好的特点,将SWCNTs与PMMA一起分散在二氯化苯(DCB)溶液中,运用光学诱导作用将SWCNTs吸附在单模光纤(SMF)端面,并加热固化成膜。在光纤激光器环形腔结构中引入SWCNT/PMMA薄膜作为SA,获得了具有稳定的重复频率为8.366MHz的基频锁模脉冲序列,其中心波长在1 562nm,脉冲宽度为1.2ps。 相似文献
39.
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