摘要
激光探针法是捕捉超快动力学过程的主要方法之一,在等离子体物理、光化学、生物医学等领域都有着广泛的应用.本文提出一种时间波长编码的探针光产生方案,该方案通过级联不同相位匹配角的倍频晶体和独立的延迟线来实现时间波长编码,具有单次高时空分辨率、高帧率、时间窗口可调范围广、时间分辨率和时间窗口参数独立可调的优点.在实验中搭建了一套探针光产生装置,具有247 fs的时间分辨率、4μm的空间分辨率、4.05 THz的最高帧率、时间窗口从亚皮秒到3 ns可调,将该装置用于捕捉飞秒激光诱导的光丝的动力学过程,证明该探针光产生方案用于捕捉超快动力学过程的可行性.在讨论中,分析了探针光关键参数能达到的极限帧率为35.7 THz,极限时间分辨率为28 fs,时间窗口的范围可以从百飞秒到几十个纳秒进行调节.探针光的高时空分辨率和参数互相独立可调的优点,为多时间尺度的超快动力学过程的单次高时空分辨捕捉提供了一种可行方案.
The laser probe is one of the main techniques for capturing ultrafast dynamic processes and has extensive applications in fields such as plasma physics,photochemistry,and biomedical science.In this work,a time-wavelength encoded optical probe generation scheme is proposed,which uses cascaded frequency doubling crystals with different phase-matching angles and independent delay lines to achieve time-wavelength encoding.This method offers single-shot high-spatiotemporal resolution,high frame rate,and a wide range of adjustable time windows.The temporal resolution of the optical probe depends on the pulse width of the second harmonic,which can be adjusted by changing the phase-matching angle of the frequency-doubling crystal.The time window of the optical probe is only related to the change in the delay line,which can be adjusted by changing the length of the delay line.Therefore,the time resolution and time window of the optical probe are independent of each other.An optical probe generation system is constructed with 247 fs temporal resolution,4μm spatial resolution,4.05 THz maximal frame rate,and an adjustable time window from sub-picosecond to 3 ns.The three-dimensional spatiotemporal evolution process of plasma filaments is captured within a single shot by using the optical probe.The experimental results show that the ionization front of the plasma propagates forward at a velocity of(2.963±0.024)×10~8 m/s,which is consistent with the theoretical prediction.This demonstrates the feasibility of using the probe for capturing ultrafast events.In the part of discussion,we analyze that the key parameters of the optical probe can reach a maximum frame rate of 35.7 THz,a maximum time resolution of 28 fs,and a time window range that can be adjusted from hundreds of femtoseconds to tens of nanoseconds.Finally,the optimal design parameters of the optical probe are given for different application scenarios.The optical probe generation scheme has good scalability and versatility,and can be combined with any wavelength de
作者
易友建
丁福财
朱坪
张栋俊
梁潇
孙美智
郭爱林
杨庆伟
康海涛
姚修宇
李兆良
谢兴龙
朱健强
Yi You-Jian;Ding Fu-Cai;Zhu Ping;Zhang Dong-Jun;Liang Xiao;Sun Mei-Zhi;Guo Ai-Lin;Yang Qing-Wei;Kang Hai-Tao;Yao Xiu-Yu;Li Zhao-Liang;Xie Xing-Long;Zhu Jian-Qiang(Key Laboratory of High Power Laser and Physics,Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China;Center of Materials Science and Optoelectronics Engineering,University of Chinese Academy of Sciences,Beijing 100049,China;School of Physics,Xi’an Jiaotong University,Xi’an 710049,China;School of Optical-Electrical and Computer Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2023年第22期102-110,共9页
Acta Physica Sinica
基金
国家自然科学基金(批准号:12004403,12074399,12204500)
中国科学院(批准号:XDA25020105,181231KYSB20170022,CXJJ-21S015)
上海市科委科技基金(批准号:22YF1455300,20ZR1464400)
科学技术部基金(批准号:2021YFE0116700)资助的课题。
关键词
单次
波长时间编码
高时空分辨
全光学探针
single-shot
time-wavelength encoding
high spatiotemporal resolution
all-optical probe
