Author Affiliations
Abstract
1 Shenzhen University, College of Physics and Optoelectronic Engineering, Shenzhen Key Lab of Micro-Nano Photonic Information Technology, Shenzhen, China
2 Shenzhen University, College of Electronic Information Engineering, Shenzhen, China
3 Institut National de la Recherche Scientifique, Centre Énergie Matériaux Télécommunications, Laboratory of Applied Computational Imaging, Varennes, Québec, Canada
We report a framing imaging based on noncollinear optical parametric amplification (NCOPA), named FINCOPA, which applies NCOPA for the first time to single-shot ultrafast optical imaging. In an experiment targeting a laser-induced air plasma grating, FINCOPA achieved 50 fs-resolved optical imaging with a spatial resolution of ～83 lp / mm and an effective frame rate of 10 trillion frames per second (Tfps). It has also successfully visualized an ultrafast rotating optical field with an effective frame rate of 15 Tfps. FINCOPA has simultaneously a femtosecond-level temporal resolution and frame interval and a micrometer-level spatial resolution. Combining outstanding spatial and temporal resolutions with an ultrahigh frame rate, FINCOPA will contribute to high-spatiotemporal resolution observations of ultrafast transient events, such as atomic or molecular dynamics in photonic materials, plasma physics, and laser inertial-confinement fusion.
ultrafast imaging spatiotemporal resolution frame rate noncollinear optical parametric amplification Advanced Photonics
2020, 2(5): 056002
Author Affiliations
Abstract
1 Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology, College of Physics and Optoelectronics Engineering, Shenzhen University, Shenzhen518060, China
2 College of Electronic and Information Engineering, Shenzhen University, Shenzhen518060, China
A tunable ultrafast intensity-rotating optical field is generated by overlapping a pair of 20 Hz, 800 nm chirped pulses with a Michelson interferometer (MI). Its rotating rate can be up to 10 trillion radians per second ($\text{Trad}/\text{s}$), which can be flexibly tuned with a mirror in the MI. Besides, its fold rotational symmetry structure is also changeable by controlling the difference from the topological charges of the pulse pair. Experimentally, we have successfully developed a two-petal lattice with a tunable rotating speed from $3.9~\text{Trad}/\text{s}$ up to $11.9~\text{Trad}/\text{s}$, which is confirmed by our single-shot ultrafast frame imager based on noncollinear optical-parametric amplification with its highest frame rate of 15 trillion frames per second (Tfps). This work is carried out at a low repetition rate. Therefore, it can be applied at relativistic, even ultrarelativistic, intensities, which usually operate in low repetition rate ultrashort and ultraintense laser systems. We believe that it may have application in laser-plasma-based accelerators, strong terahertz radiations and celestial phenomena.
noncollinear optical-parametric amplification rotating rate ultrafast frame imager ultrafast intensity-rotating optical field High Power Laser Science and Engineering
2020, 8(1): 010000e3
山东大学信息科学与工程学院，山东 济南 250100
飞秒光参量放大技术是一种获得宽带飞秒脉冲的有效手段。首先介绍了飞秒光参量放大技术的基本原理，并通过数值模拟显示了群速度失配及位相失配对信号转换过程的影响。数值计算结果表明：群速度失配及位相失配会导致转换效率下降，群速度失配还会导致脉冲发生畸变。其次，综述了该技术在超短脉冲特别是周期量级脉冲产生方面的研究进展，并介绍了Baltuska等设计的可以产生3．9fs脉冲的非共线光参量放大装置。其中，详细讨论了超连续白光注入源、泵浦光角色散以及晶体选择三方面内容。最后介绍了该技术在高能飞秒脉冲产生方面取得的最新研究进展。
非线性光学 飞秒光参量放大 周期量级脉冲 超连续白光 泵浦光角色散 非共线光参量放大 高能飞秒脉冲 nonlinear optics femtosecond optical parametric amplification few-cycle pulse supercontinuum angular dispersion of pump beam noncollinear optical parametric amplification high-power femtosecond pulse
1 深圳大学物理科学学院应用物理系, 深圳 518060
2 华东师范大学光谱学与波谱学教育部重点实验室, 上海 200062
基于非共线光参量放大,以波长800 nm飞秒激光的倍频光为抽运光,以激光二极管640 nm连续波激光为信号光,产生了与800 nm飞秒激光精确同步的无直流本底的1064 nm脉冲光。实验结果显示该1064 nm的光脉冲在脉冲能量和空间光束质量上均可作为1064 nm波长脉冲放大器的种子光。仅通过一级简单紧凑的非共线参量放大就可实现光周期量级的光参量啁啾脉冲放大系统的抽运激光和种子光的精确同步。
非线性光学 非共线光参量放大 光参量啁啾脉冲放大 时间同步
