利用砷化镓表面的二次谐波测量ps激光的脉宽

介绍利用GaAs晶体的<111>面和<110>面产生的二次谐波来测量超短脉冲宽度的原理、装置和实验结果,并与TPF和THG方法测量的结果进行了比较,三种方法测得的结果完     

二次谐波法测量飞秒单脉冲脉宽

碰撞锁模(CPM)环形染料激光系统中,通过棱镜色散对脉冲啁啾补偿,获得约60fs的超短脉冲输出,其平均功率为5mW、单脉冲能量约为0.1nJ。应用它有必要先进行脉冲放大。飞秒脉冲放大后的脉冲特性     

智能化ps脉宽测量仪

介绍一种自动测量和数据处理的智能化非共线二次谐波脉宽测量设备。自相关测量装置的延迟棱镜由智能化电路(以TP-801A单板机为主体,加上若干组件构成)控制的步进电机驱动,步长可调,最小步长为10μm,时间分辨率优于0.1ps。测量步数和每步的重复测量次数可以任意选定。每次测量的结果自动归一化。打字机自动给出每步测量的平均值和偏差范     

利用非共线二次谐波的产生测量ps光脉冲的形状和宽度

本文介绍了通过取样光脉冲与待测光脉冲在KDP晶体中非共线二次谐波的产生,测量ps光脉冲的形状和宽度的原理、装置和实验结果,并与自相关测量法进行了比较,给出了使用相关法测脉宽中的修正因子曲线。     

利用染料增益测量激光脉宽的简单方法

通常测量ns最级激光脉宽,均采用快速光电元件配以宽带示波器进行。然而一般实验室不具备这样的设备条件。而且,例如氮分子激光器运转时的电磁辐射还严重地干扰示波器的正常工作,需要屏蔽室才行。这里介绍的方法不需使用较高级的宽带示     

深紫外飞秒激光脉宽测量

为准确测量193 nm深紫外飞秒激光的脉冲宽度,基于氟化钙的双光子荧光效应,设计并搭建了用于紫外飞秒激光脉冲的脉宽测量系统。双光子荧光信号强度与入射激光光强的平方依赖关系证明了获得双光子荧光信号的可靠性。利用插入法进行了CCD探测系统的数值标定,获得单像素对应的时间尺度为7.35 fs。单脉冲测量下,得到193 nm深紫外飞秒激光的脉宽为476.1 fs,与利用光谱法进行测量计算得到的结果基本吻合。     

改制调试脉宽50KW发射机抑制输出二次谐波网络

改制调试脉宽５０ＫＷ发射机抑制输出二次谐波网络李常岭，杨华涛（呼盟广播电台７５３台）引言我台９２年引进的脉宽５０ＫＷ发射机，已试播一年多，在此期间，我们体会该机比较稳定，主观收听效果反映较好，但机器的个别部位，由于设计和工艺原因也有些不尽人意之处，较...     

0.825 THz砷化镓单片集成二次谐波混频器

基于国内的GaAs单片集成电路产线,研制了一款中心频率在0.825 THz的二次谐波单片混频器。针对肖特基二极管在太赫兹频段的高频效应详细分析了反向并联肖特基二极管的寄生参数以完善单片电路的设计。单片电路集成度高和装配误差小的特性更适用于太赫兹频段器件的设计。梁氏引线形式电路设计既可以降低介质基板带来的损耗,减小安装的位置偏移。实测结果表明, 0.825 THz单片混频器最佳单边带的插损值为28 dB,0.81到0.84 THz频率范围内插损小于33 dB。     

High-power picosecond pulse generation in GaAs multiquantum well phase-locked laser arrays using pulsed current injection

Gaussian shaped picosecond pulses as short as 62 ps have been obtained from an array of 10 phase-coupled multiquantum well GaAs lasers. Combined dc and 75 ps long current pulses from a comb generator were used. Single pulses were obtained with an average power of 50 mW at a 960 MHz repetition rate which corresponds to a peak power of 0.8 W. These pulse widths are in good agreement with a theory of pulse formation based on the carrier and photon density equations with the gain expanded in a power series in time to yield Gaussian pulses.     

Electrostrictive self-focusing of picosecond laser pulse trains

A nanosecond-long train of picosecond laser pulses theoretically can produce self-focusing by electrostriction, even though the trapping threshold for a single picosecond pulse is very high. The relative roles of electrostriction and various types of Kerr effect in picosecond pulse train self-focusing should be assessed.     

对同步泵浦染料激光器系统已有实验结果的解释和讨论

给出的同步泵浦染料激光脉冲的理论结果作一些讨论和解释,特别是该理论证实的同步泵浦染料激光脉冲的宽度与功率均存在最佳值的问题。     

Measurement of on-chip waveforms and pulse propagation in digital GaAs integrated circuits by picosecond electro-optic sampling

We demonstrate precise measurement of sub-100 ps rise time on-chip electrical waveforms and of pulse propagation in digital GaAs integrated circuits with the use of picosecond electro-optic sampling. These experiments yield the first non-invasive measurement of single-gate propagation delays via direct and precise observation of on-chip waveforms at the input and output of individual logic gates internal to an integrated circuit.     

Self-Q-switched picosecond optical pulse generation with tandem-type AlGaAs TJS laser

Experimental results are presented for ultrashort optical pulse generation by an AlGaAs tandem-type laser with transverse junction stripe structure. The shortest optical pulse width of 14 ps was observed by an ultrafast streak camera, while typical pulse widths were about 20 ps. Further shorter pulses may be expected with this type of semiconductor laser by adequate control of the saturable absorber region.     

High-order harmonic generation from a solid surface plasma by usinga picosecond laser

Investigations have been performed on harmonic generation from solid-vacuum interfaces using a prepulse-free 2.2-ps 1054-nm laser pulse at maximum intensities of ~1×10¹⁵ W·cm^-2 . The harmonic intensities were strongest for p-polarized pump and dropped to about 50% in the case of s-polarized pumps. The ratio I_4wI_2w between the intensities of the fourth and second harmonics was 0.25 at Iλ²=6×10¹⁴ W·cm^-2·μm², which is relatively large when compared with the value predicted by simulations. The harmonics are collimated in the specular direction, with a transverse mode and divergence comparable to that of the driving laser     

Multiwavelength 10-GHz picosecond pulse generation from asingle-stripe semiconductor diode laser

A single-stripe GaAs-AlGaAs semiconductor optical amplifier (SOA) has been used to generate four tunable wavelength-division multiplexed (WDM) channels simultaneously, each transmitting 12-ps pulses at 2.5 GHz, for an aggregate pulse rate of 10 GHz. Wavelength tuning over 18 nm has been demonstrated with channel spacing ranging from 0.8 to 2.1 nm. A potential spectral correlation across the multiwavelength spectrum has been studied in both experiment and simulation methods. These results show the potential for utilizing single stripe laser diodes as multiwavelength sources in WDM-TDM network     

Tunable dual-wavelength picosecond optical pulses generated from aself-injection seeded gain-switched laser diode

A novel scheme to generate dual-wavelength picosecond optical pulses has been demonstrated. The pulses are obtained by self-injection seeding of a gain-switched laser diode simultaneously at two different wavelengths. Optical feedback is provided by a partially reflecting fiber mirror. Single-mode pulses at alternate wavelengths around 1.3 μm have been generated. The pulse width varies from about 40 to 50 ps. The output wavelengths can be tuned by changing the electrical modulation frequency. Spacing between the wavelengths can also be controlled by adjusting the length of the dispersive fiber cavity. Our experimental data are in good agreement with the calculated results     

High-peak-power picosecond optical pulse generation from highly RF-modulated InGaAsP DH diode laser

The feasibility for generating high-peak-power ultrashort optical pulses was demonstrated from a highly RF-modulated InGaAsP DC-PBH laser diode at 1.3 ?m for the first time. Measured pulse width is found to be approximately 28 ps at 7 mW averaged output power, and peak output power reached about 1.2 W at 210 MHz repetition frequency. Higher peak output and shorter optical pulses could be expected with this type of semiconductor diode laser in the near-infra-red region.     

Bandwidth limited picosecond optical pulse generation from actively mode-locked AlGaAs diode laser

A simple configuration made of a conventional AlGaAs diode laser without antireflection coating combined with an external reflector and an optical etalon was proved to be practically feasible to generate bandwidth limited mode-locked optical pulses of 30 ps duration by synchronous modulation at the external cavity mode interval. Generated optical pulse shape was found to be Lorentzian rather than Gaussian for the first time, based on the measurements of both the s.h.g. correlation method and the ultrafast streak camera.