共查询到19条相似文献,搜索用时 140 毫秒
1.
2.
新型电光陶瓷调Q光纤激光器 总被引:2,自引:2,他引:0
报道了基于OptoCeramic(R)电光陶瓷材料的新型调Q光纤激光器.采用976 nm半导体激光器作为抽运源,电光陶瓷调制器作为Q开关,峰值吸收系数1200 Db/m的高掺杂镱纤作为增益介质构成环形腔激光器.增益光纤的高掺杂浓度使得激光器的腔长得到缩短,输出光脉冲的宽度得到压缩.通过调节电光元件的电压,控制材料的折射率,调节谐振腔的损耗,实现Q开关作用.实验中通过改变腔长、抽运功率和重复频率,研究了脉冲的输出特性.获得最窄脉宽104 ns,重复频率3~40 kHz连续可调的调Q脉冲输出. 相似文献
3.
报道了利用脉宽可调的光子晶体光纤飞秒激光放大器抽运矩形波导结构的GaP晶体太赫兹(THz) 发射器产生频率可调谐的超快THz脉冲.非线性晶体中光整流过程产生的THz辐射频率随抽运光脉冲宽度而 变化. GaP波导THz发射器可通过波导的几何尺寸来控制色散,以达到增加有效作用长度和提高输出功率的目的. 不同横截面尺寸的波导型发射器的THz辐射峰值频率随相位匹配条件的改变而改变,加以脉宽调节技术, 可以在大频谱范围获得频谱精细可调的THz脉冲.实验中在1 mm×0.7 mm的波导型THz发射器中获得了 频率可调谐的THz脉冲.提出实现THz辐射频率大范围调谐的GaP波导型阵列发射器的实施方案. 相似文献
4.
《中国光学》2020,(3)
本文开展了基于半导体光开关技术实现超短脉宽CO_2激光输出的物理机制研究。首先,在分析光生载流子过程及载流子复合扩散机制的基础上,引入直接吸收、俄歇复合、等离激元辅助复合以及双极扩散等物理过程,并基于Drude理论,完善了半导体光开关理论模型。其次,利用该模型对两级半导体光开关产生超短CO_2脉冲机制进行了数值模拟及分析,结果显示该模型与国外最新实验结果一致,表明了模型的合理性与正确性。最后,利用该模型分析了控制光脉冲宽度对两级光开关工作效率的影响,发现短的控制光脉冲更有利于精确、高效地截取出高质量的超短CO_2脉冲。本文研究证明半导体光开关法是实现超短CO_2激光脉宽可调输出的有效技术途径。 相似文献
5.
6.
7.
介绍了一种用于里德伯原子激发的纳秒脉冲激光系统.实验利用两个kHz线宽的1018 nm连续激光器作为种子源,通过两个20 GHz带宽的光纤调制器产生时间分离的脉冲激光;脉冲激光经掺镱光纤放大器后输出峰值功率约4600 W,单次穿过PPLN(周期极化铌酸锂)晶体倍频获得509 nm脉冲激光,典型脉冲激光峰值功率约173 W.该激光系统单路输出脉冲重复频率在300 kHz—100 MHz范围连续可调,脉宽在1—100 ns范围连续可调.该509 nm激光在聚焦条件下可以实现GHz带宽的铯原子里德伯态激发. 相似文献
8.
9.
10.
11.
介绍了一种可以完成脉宽、幅值、频率可调、十路脉冲输出且延时可调功能的程控脉冲发生器。硬件主要包括主电源和辅助电源、功率放大电路、控制系统处理器、数字键盘和液晶显示屏。该脉冲发生器输出脉冲宽度可在1~30 s间调节,脉冲幅值在1~15 V间调节,输出脉冲频率范围为1 Hz~30 kHz,十路脉冲输出中每路脉冲之间可以在0~1 ms范围内精确调节。该脉冲发生器可为多个脉冲源的并联运行提供延时触发,为多个绝缘栅双极型晶体管(IGBT)开关串联提供同步触发。 相似文献
12.
A.K. Sharma R.K. Patidar M. Raghuramaiah P.A. Naik P.D. Gupta 《Optics Communications》2011,284(19):4596-4600
A simple technique is presented to generate temporally flat-top shaped laser pulses using electro-optic modulator (Pockels cell). It involves splitting of input laser pulse into two halves of equal intensity and then stacking together with appropriate optical delay to get a temporally flat-top laser pulse. It also allows generation of other pulse shapes by varying the relative intensity, delay, and phase between two halves of the input laser pulse. Temporally flat-top laser pulses of duration ~ 9 ns have been generated using ~ 7 ns duration incident laser pulses from a flash lamp pumped Q-switched Nd:glass laser oscillator. The rise and fall-time of the shaped pulse is limited by speed of electro-optic switch (Pockels cell), which is ~ 2 ns in the present case. 相似文献
13.
介绍了一种基于Marx发生器原理设计的200 kV闪光照相测试系统,该系统具有延时功能,可按照实验要求,在预定时刻产生脉冲X射线进行闪光照相测试。设计了一台10级同轴结构的Marx发生器,采用了正负极充电,极间电容耦合为Z形回路的Marx发生器线路,利用开关与屏蔽外筒间的结构电容来锐化高压脉冲的输出,同时采用紧凑性、低电感设计获得窄脉冲的输出。在充电电压为25 kV的情况下,75 的负载上获得了脉宽小于100 ns、幅度大于200 kV的高压脉冲,通过高压电缆驱动闪光X射线二极管, 在距光源25 cm处获得了剂量大于910-6 C/kg、脉冲宽度约为70 ns的闪光X射线。 相似文献
14.
报道了用半绝缘GaAs光电导开关产生电压幅值稳定、ps量级时间晃动超快电脉冲的实验结果.分别用ns,ps和 fs激光脉冲触发GaAs光电导开关的结果表明,在低电场偏置下,电极间隙为1 mm的GaAs光电导开关可以产生触发时间晃动小于10 ps、电压幅值变化小于1.2 %、亚ns量级脉冲宽度的稳定超短电脉冲.分析了触发光脉冲能量起伏对光电导开关产生超快电脉冲电压幅值的影响,指出通过控制光电导开关的触发条件和对开关的优化设计,就可以获得电压幅值稳定、时间晃动在ps量级的超快电脉冲.
关键词:
光电导开关
超快电脉冲
电压幅值稳定性
时间晃动 相似文献
15.
16.
Based on electro-optic switch effect in crystal, a novel laser ranging method is proposed. CW-laser emitted by laser transmitter propagates forward to the measured target, after being reflected by the target, and then goes back to the transmitter. Close to the transmitter, a special mono-block LiNbO3 crystal is added into the round-trip light beams. High-voltage pulses with the sharp enough changes in rising edges are loaded on the crystal. Based on electro-optic effect, double refraction and internal double reflection effect in crystal, the crystal cuts off the round-trip light beams, and reflects a light pulse cut out by the crystal to a detector aside from the original beam path. The pulse width T is the period that laser propagates forward and back between the crystal and the target. The feasibility of the new idea is proved by our experiments and a brand-new way for the laser ranging is provided. 相似文献
17.
18.
19.
Kusama H. Yagi T. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1997,25(6):1431-1434
A coaxial Marx generator triggered with a UV laser pulse propagating coaxially through multigap switches is constructed. The Marx generator is operated at maximum voltage of 200 kV with a rise time of less than 10 ns. To trigger multigap switches in the Marx generator, the laser pulse is passed through fine metal mesh fitted in the holes formed along the central axis in electrodes of gap switches. Photoelectrons generated from the mesh part of the cathode trigger the discharge and close the switches. Timing jitter of the high voltage pulse with respect to the laser pulse is 800 ps for the case of single gap switch and 1 ns for the Marx generator with two stage gap switches. Since the spark path is always formed from the solid surface of the cathode instead of the metal mesh, the mesh part of the cathode is never damaged for a large number of shots, promising long lifetime of the electrodes 相似文献