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1.
Ultrashort optical pulse generation using a fiber FM laser is presented and analyzed in detail. Fiber FM laser operation is realized using a fiber ring with an internal phase modulator and an erbium-doped fiber amplifier. To compress FM laser pulses, an external dispersive single-mode fiber is employed. Furthermore, by external intensity modulation, the pulse background is removed. The background ratio of the generated ultrashort pulse is calculated and compared with the experimental results. The experimental results show an output optical pulse width of 1.77 ps and a spectral bandwidth of 0.5 THz. 相似文献
2.
A method of tunable, high repetition-rate optical pulse generation by using optical injection locking of semiconductor lasers has been described in this paper. This method utilizes the superposition of five coherent optical carriers obtained from the spectrum of optical phase modulation, which results in a sharp optical pulse. Theoretical calculations indicate that a pulse width of 1 ps and a repetition rate of 200 GHz can be achieved for a modulator drive frequency of 40 GHz. PACS 42.79.Sz; 42.79.Hp; 42.79.-e; 42.62.-b; 85.60.-q 相似文献
3.
采用超低压(22×102Pa)选择区域生长(selective area growth, SAG)金属有机化学气相沉积(metal-organic chemical vapor deposition, MOCVD)技术成功制备了InGaAsP/InGaAsP 级联电吸收调制器(electroabsorption modulator, EAM)与分布反馈激光器(distributed feedback laser, DFB)单片集成光源的新型光电器件.实验结果表明,采用该技术制备的器件
关键词:
超低压
选择区域生长
集成光电子器件
超短光脉冲 相似文献
4.
A high-quality low-timing-jitter 20-GHz optical pulse train is generated by using two cascaded sinusoidally driven electroabsorption modulators (EAMs) at very low bias voltage of -0.8 V in conjunction with a tunable distributed feedback (DFB) semiconductor laser. An approximate transform-limited optical pulse,with the pulse width less than 7 ps, the spectral width of 0.3 nm, and the side-mode suppression ratio (SMSR) above 20 dB, is obtained by tuning the optical delay line. 相似文献
5.
An actively mode-locked laser with tunable repetition rate is proposed and experimentally demonstrated based on a programmable electrical pattern generator. By changing the repetition rate of the electrical patterns applied on the in-cavity modulator, the repetition rate of the output optical pulse sequences changes accordingly while the pulse width of the optical pulse train remains almost constant. In other words, the output ultra-short pulse train has a tunable duty cycle. In a proof-of-principle experiment, optical pulses with repetition rates of 10, 5, 2.5 and 1.25 GHz are obtained by adjusting the electrical pattern applied on the in-cavity modulator while their pulse widths remain almost unchanged. 相似文献
6.
We propose and demonstrate generation of an in-phase optical pulse train from an optical beat signal. The proposed method is based on four-wave mixing occurring between the two continuous waves of the beat signal and on spectral filtering to shape the spectrum to be symmetric about the carrier frequency. We perform an experiment to verify the proposed method and obtain a 1.5 ps width in-phase pulse train from a 160 GHz beat signal. Furthermore, we employ a pulse compression scheme to reshape and compress the obtained pulse train, and we show that a 160 GHz repeating, 0.7 ps FWHM, nearly transform-limited, in-phase sech pulse train is successfully generated. 相似文献
7.
We demonstrate a novel technique for the generation of mode-locked pulses from a continuous-wave (cw) optical parametric oscillator (OPO). The technique is based on the deployment of a phase modulator in combination with an antiresonant ring interferometer internal to a cw OPO, simultaneously providing spectral broadening and phase-to-amplitude feedback modulation. The scheme is implemented in a doubly-resonant cw OPO based on MgO:sPPLT, configured in a standing-wave cavity and pumped at 532 nm. With the phase modulator activated and the cavity length synchronized, a stable train of 800 ps pulses is generated at a repetition rate of 160 MHz. Using single-pass second harmonic generation (SHG) of the OPO output, we observe a four times enhancement in SHG compared with cw operation, confirming the real achievement of energy concentration as a result of mode-locked operation. 相似文献
8.
We propose and demonstrate a fiber-based phase-only filtering technique for programmable optical pulse shaping, in which the filtering operation is implemented in the time domain by means of an electro-optical (EO) phase modulator. The technique has been applied for generating customized ultrahigh-repetition-rate optical pulse sequences (>40 GHz) from single input pulses by driving the EO phase modulator with a periodic electronic waveform (RF tone). The generated output pulses are replicas of the input pulse and both the repetition rate and the envelope profile of the generated sequences can be controlled and tuned electronically using this approach. 相似文献
9.
10.
H. Wang M. Chini Y. Wu E. Moon H. Mashiko Z. Chang 《Applied physics. B, Lasers and optics》2010,98(2-3):291-294
We compressed high-power laser pulses to 5 fs and 0.5 mJ using a neon-filled hollow-core fiber and a high-throughput 4f system. The carrier–envelope phase of the two-cycle pulses was measured directly by using their over-one-octave output spectrum. The carrier–envelope phase was stabilized by feedback controlling the grating separation of a stretcher in a chirped pulse amplifier. To the best of our knowledge, this is the first time that carrier–envelope phase locked few-cycle pulses were generated by using an adaptive phase modulator. 相似文献
11.
Han Yang XiangSheng Liu Jian Du Wei Sun DeHui Li MaoBin Yi GuoTong Du 《Optics & Laser Technology》2005,37(1):55-60
Optical pulse generated by directly modulated distributed feedback (DFB) laser and external electro-absorption modulator (EAM) in virtue of the method of fringe-resolved second-harmonic generation correlation was measured. Without the pulse's shape being assumed, through the method of iterative reconstruct interference signal, the waveform and phase of the pulse was reconstructed. The full-wave at half-maximum (FWHM) of the pulse generated by EAM under the microwave modulation of 2.5 GHz is 30.8 ps, whose shape is close to that of the sech2-type pulse. The FWHM of the pulse generated by DFB laser is 18.3 ps, whose shape is close to that of the Lorenz-type pulse. And the original chirping of EAM is smaller than that of DFB laser. 相似文献
12.
采用基于平衡光学互相关的超快激光绝对距离测量方法对大气中一段15m的空间距离进行了测量。仿真了不同脉冲宽度、不同光强损耗对平衡互相关信号的影响,理论分析表明脉宽展宽对平衡互相关信号影响较大。采用中心波长为1037nm、重复频率为260MHz的超快激光器光源,搭建了测距系统。实验验证了在脉宽分别为1.44ps、132fs时,对平衡互相关信号的影响,实验结果符合理论分析。研究了不同脉冲宽度对测量分辨力的影响,结果显示,采样时间为5ms,脉宽为1.44ps,测量分辨力不低于50μm;而当脉宽为132fs时,测量分辨力优于5μm。 相似文献
13.
14.
提出了一种新型的基于光电振荡器的重复频率可调谐的超低抖动光窄脉冲源. 光电振荡器系统可以产生超低相位噪声的微波信号; 被该信号调制的直调光经过两次相位调制之后, 使光脉冲的啁啾增强; 再通过一段色散补偿光纤, 光脉冲被进一步压窄. 实验中使用YIG可调滤波器, 可以得到8–12 GHz内步进为200 MHz的可调谐微波信号, 因此光脉冲的重复频率具有可调谐性. 当微波信号即脉冲重复频率为9.6 GHz时, 测得脉冲宽度为3.7 ps, 相位噪声为-130.1 dBc/Hz@10 kHz. 由此得出光脉冲的瞬时抖动为60.1 fs (100 Hz–1 MHz), 因此该方案产生的光窄脉冲源具有超低的抖动. 相似文献
15.
利用单模光纤中的光弹效应和交叉相位调制(XPM)效应,提出了一种频率分辨光学开关法测量超短脉冲的新方案.在本方案中,单模光纤的前一部分产生可变延迟,后一部分作为非线性介质产生非线性效应.该方案只需一根单模光纤,无须复杂的光路校准,结构简单,损耗低;光纤中的XPM效应易发生,无须相位匹配.对提出的方案进行了数值模拟,采用基于矩阵的主元素广义投影算法,恢复出待测脉冲的幅度和相位信息,并研究了光纤长度和待测超短脉冲的脉冲宽度对测量结果的影响.结果表明:测量准确度随着光纤长度的增加而提高,选取长度为2 km的光纤,就可以实现对超短脉冲的准确测量;本文方案适用于脉冲宽度不小于80 fs的超短光脉冲的测量. 相似文献
16.
10 GHz clock recovery from 40 Gbps optical time-division-multiplexed (OTDM) signal pulses is experimentally demonstrated using optical phase lock loop based on a terahertz optical asymmetric demultiplexer (TOAD) with a local-reference-oscillator-free electronic feedback circuit. The clock pulse that was used as the control pulse had energy of 800 fJ and the SNR of the time-extracted 10 GHz RF signal to the side components was larger than 40 dB. 相似文献
17.
A novel method for generating ultrawideband (UWB) monocycle pulses based on cross-gain modulation (XGM) in a semiconductor optical amplifier (SOA) is proposed and experimentally demonstrated. Thanks to the XGM in the SOA, a pair of polarity-reversed optical Gaussian pulses is generated at the output of the SOA, to which a Gaussian pulse pump and a continuous-wave probe are applied. The two polarity-reversed optical pulses are then time delayed by two cascaded fiber Bragg gratings to introduce a time delay difference. A UWB monocycle pulse with a full width at half-maximum of 48 ps and a fractional bandwidth of 188% is generated at the output of a high-speed photodetector. 相似文献
18.
We have generated femtosecond subharmonic pulses by using an optical parametric oscillator. The optical frequencies of the idler and the signal are one third and two thirds, respectively, of the optical frequency of the pump pulse. The carrier phase of the signal pulse relative to that of the pump pulse was locked by electronic feedback. The carrier-envelope phase slip frequency of the signal pulse relative to that of the pump was locked to F/6 , where F is defined as the repetition frequency. 相似文献
19.
We present a novel system design that can generate the optimized wavelength-tunable optical pulse streams from an uncooled gain-switched Fabry–Perot semiconductor laser using an optical amplifier as external light source. The timing jitter of gain-switched laser has been reduced from about 3 ps to 600 fs and the pulse width has been optimized by using our system. The stability of the system was also experimentally investigated. Our results show that an uncooled gain-switched FP laser system can feasibly produce the stable optical pulse trains with pulse width of 18 ps at the repetition frequency of 5 GHz during 7 h continuous working. We respectively proved the system feasibility under 1 GHz, 2.5 GHz and 5 GHz operation. 相似文献