作者：
Lu Shi-Zhuan*;You Kai-Ming;Chen Lie-Zun;Wang You-Wen;Yang Hui;...
期刊：
物理学报,2012年61(23):209-216 ISSN：1000-3290
通讯作者：
Lu Shi-Zhuan
作者机构：
[Chen Lie-Zun; Yang Hui; You Kai-Ming; Wang You-Wen; Dai Zhi-Ping; Lu Shi-Zhuan] Hengyang Normal Univ, Dept Phys & Elect Informat Sci, Hengyang 421008, Peoples R China.
通讯机构：
[Lu Shi-Zhuan] H;Hengyang Normal Univ, Dept Phys & Elect Informat Sci, Hengyang 421008, Peoples R China.
作者机构：
[唐益群; 王友文; 陆世专; 游开明; 陈列尊; 张登玉] Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang 421008, China
通讯机构：
Department of Physics and Electronic Information Science, Hengyang Normal University, China
关键词：
非线性传输;啁啾脉冲;宽带激光;时空调制
摘要：
为避免啁啾脉冲堆积宽带激光的空间调制对光学元件的损坏, 数值研究了其非线性传输过程中时域调制对光束空间调制产生与增长的影响。结果表明：光束未叠加空间调制时, 若B积分在实际工作范围内, 堆积子脉冲间干涉引入时间调制外, 叠加与未叠加时间调制, 正反常色散情况下光束空间上均不会产生调制, 因而也没有调制增长, 然而, 当B积分进一步增加时, 光束空间将产生调制, 并能快速增长；当光束引入空间调制后, 在反常色散情况下, 与时间未额外叠加调制相比, 时间额外叠加调制时空间调制增长速度明显加快, 而在正常色散时, 额外添加时间调制与不添加调制, 空间调制增长的差别很小。 To identify the potential risks of spatial modulation of broad-band laser beams stacked by chirped pulses on the safety of optics, this paper numerically investigated the effect of temporal modulation on the generation and growth of spatial modulation during its nonlinear propagation. When there is no additional spatial modulation and the B integral is limited in the practical working range (usually less than 2.0 rad), no spatial modulation will be generated for both normal dispersion and anomalous dispersion; while with the B integral further increasing, spatial modulation will emerge with a rapid growth. When there is additional spatial modulation for anomalous dispersion, the spatial modulation with additional temporal modulation will grow more quickly than that without additional temporal modulation. However, for normal dispersion, the growth of spatial modulation for both cases is similar.
摘要：
In this paper, precise synchronization of the femtosecond and picosecond laser regenerative amplifiers with different wavelengths and independent seed oscillators was achieved using the electronic phase-locked loop and global clock techniques. The root-mean-square relative timing jitter of the two regenerative amplifiers was measured as 0.66 ps using a modified statistical method based on the error propagation relation between the independent variables and the conventional optical cross-correlation technique. The results suggest that this method is more accurate and requires simple optical setups for low-pulse repetition rate lasers.
摘要：
Based on the full two-dimensional characteristics of the quasi-phase-matched fan-out periodically poled crystal, a scalable and engineerable scheme for ultrabroadband optical parametric chirped-pulse amplification is proposed, which can significantly broaden the gain bandwidth by the spatial separation of different frequency components of the signal pulse and manipulation of the distribution of the pump beam along the fan-out direction of the crystal. The theoretical analysis shows that the signal pulse can be amplified with minimal spectrum narrowing, and the initial spectrum can be broadened considerably if needed. Based on this scheme, using a fan-out periodically poled 5% mol MgO-doped congruent lithium niobate with a configuration of 5×0.5×5 mm3 and two pump beams, the 3.3−μm middle-infrared ultrabroadband optical parametric chirped-pulse amplifier is designed. The numerical computation results confirm that the −3 dB gain bandwidth of this amplifier exceeds 320 nm and can be further broadened.
作者机构：
[王友文; 范滇元] School of Physics and Microelectronics Science, Hunan University, Changsha 410082, China;[王友文; 陈列尊] Department of Physics and Electronic Information Science, Hengyang Normal University, Hengyang 421008, China;[王友文; 邓剑钦; 文双春; 范滇元; 章礼富; 陈列尊; 傅喜泉; 张进] Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education, School of Computer and Communication, Hunan University, Changsha 410082, China
通讯机构：
School of Physics and Microelectronics Science, Hunan University, China
关键词：
啁啾脉冲;宽带激光;非线性传输;时域调制
摘要：
为避免时域调制增长形成的高强度时间尖峰对光学元件的损坏,数值研究了啁啾堆积脉冲宽带激光非线性传输的时域调制增长规律。结果表明:对于正常色散介质, 子脉冲间干涉引入的时间调制与外加调制随着传输距离的增加, 不断振荡减弱; 相反, 对于反常色散介质, 无外加时间噪声时, 堆积子脉冲间的相互干涉引入的时间调制有微弱增长, 但当传输距离进一步增加时, 子脉冲间干涉引入的调制可以获得快速增长; 而当外加非线性最快增长时间调制时, 时间调制发生迅速增长,具有破坏威胁的时间尖峰易于形成。 Characteristics of the temporal modulation riding on broad-band lasers stacked by chirped pulses are numerically investigated in nonlinear propagation. For the case of normal dispersion, the temporal modulations induced by interference among pulses and added artificially to simulate the noise weaken gradually with the increase of the propagation distance. For the case of anomalous dispersion, the temporal modulations induced by interference among pulses grow slowly at first, and start to grow rapidly after a long propagation distance; in contrast, the temporal modulations added artificially grow rapidly from the begin, indicating that the temporal peak of damage risk to the optics can be formed easily.
摘要：
We propose and implement a quasi-discrete Hankel transform algorithm based on Dini series expansion (DQDHT)in this paper. By making use of the property that the zero-order Bessel function derivative J'_0(0)=0,the DQDHT can be used to calculate the values on the symmetry axis directly. In addition,except for the truncated treatment of the input function,no other approximation is made,thus the DQDHT satisfies the discrete Parseval theorem for energy conservation,implying that it has a high numerical accuracy. Further,we have performed several numerical tests. The test results show that the DQDHT has a very high numerical accuracy and keeps energy conservation even after thousands of times of repeating the transform either in a spatial domain or in a frequency domain. Finally,as an example,we have applied the DQDHT to the nonlinear propagation of a Gaussian beam through a Kerr medium system with cylindrical symmetry. The calculated results are found to be in excellent agreement with those based on the conventional 2D-FFT algorithm,while the simulation based on the proposed DQDHT takes much less computing time.
作者机构：
[傅喜泉; 胡勇华; 王友文; 文双春; 杨华; 章礼富] College of Computer and Communication, Hunan Univ, Changsha, Hunan 410082, China;[王友文] Department of Physics and Electronic Information Science, Hengyang Normal Univ, Hengyang, Hunan 421008, China
通讯机构：
College of Computer and Communication, Hunan Univ, China
