Transient stimulated Raman scattering spectroscopy and imaging  

作　　者：Qiaozhi Yu Zhengjian Yao Jiaqi Zhou Wenhao Yu Chenjie Zhuang Yafeng Qi Hanqing Xiong 

机构地区：[1]National Biomedical Imaging Center,College of Future Technology,Peking University,Beijing 100871,China [2]Biomedical Engineering Department,College of Future Technology,Peking University,Beijing 100871,China

出　　处：《Light(Science & Applications)》2024年第4期654-663,共10页光（科学与应用)（英文版）

基　　金：This work is supported by STI2030-Major Projects 2021ZD0202500 and the National Natural Science Foundation of China 62275004.

摘　　要：Stimulated Raman scattering(SRS)has been developed as an essential quantitative contrast for chemical imaging in recent years.However,while spectral lines near the natural linewidth limit can be routinely achieved by state-of-the-art spontaneous Raman microscopes,spectral broadening is inevitable for current mainstream SRS imaging methods.This is because those SRS signals are all measured in the frequency domain.There is a compromise between sensitivity and spectral resolution:as the nonlinear process benefits from pulsed excitations,the fundamental time-energy uncertainty limits the spectral resolution.Besides,the spectral range and acquisition speed are mutually restricted.Here we report transient stimulated Raman scattering(T-SRS),an alternative time-domain strategy that bypasses all these fundamental conjugations.T-SRS is achieved by quantum coherence manipulation:we encode the vibrational oscillations in the stimulated Raman loss(SRL)signal by femtosecond pulse-pair sequence excited vibrational wave packet interference.The Raman spectrum was then achieved by Fourier transform of the time-domain SRL signal.Since all Raman modes are impulsively and simultaneously excited,T-SRS features the natural-linewidth-limit spectral line shapes,laser-bandwidth-determined spectral range,and improved sensitivity.With~150-fs laser pulses,we boost the sensitivity of typical Raman modes to the sub-mM level.With all-plane-mirror high-speed time-delay scanning,we further demonstrated hyperspectral SRS imaging of live-cell metabolism and high-density multiplexed imaging with the natural-linewidth-limit spectral resolution.T-SRS shall find valuable applications for advanced Raman imaging.

关 键 词：SCATTERING EXCITED mutually 

分 类 号：O437.3[机械工程—光学工程]