Raman scattering spectroscopy is widely used as an analytical technique in various fields,but its measurement process tends to be slow due to the low scattering cross-section.In the last decade,various broadband coher...Raman scattering spectroscopy is widely used as an analytical technique in various fields,but its measurement process tends to be slow due to the low scattering cross-section.In the last decade,various broadband coherent Raman scattering spectroscopy techniques have been developed to address this limitation,achieving a measurement rate of 500 kSpectra/s.Here,we present a substantially increased measurement rate of 50 MSpectra/s,which is 100 times higher than the previous state-of-the-art,by developing time-stretch coherent Raman scattering spectroscopy.Our newly developed system,based on a mode-locked Yb fiber laser,enables highly efficient broadband excitation of molecular vibrations via impulsive stimulated Raman scattering with an ultrashort femtosecond pulse and sensitive time-stretch detection with a picosecond probe pulse at a high repetition rate of the laser.As a proof-of-concept demonstration,we measure broadband coherent Stokes Raman scattering spectra of organic compounds covering the molecular fingerprint region from 200 to 1,200 cm^(-1).This high-speed broadband vibrational spectroscopy technique holds promise for unprecedented measurements of sub-microsecond dynamics of irreversible phenomena and extremely high-throughput measurements.展开更多
We present an interferometry setup and the detailed fringe analysis method for intense short pulse(SP) laser experiments.The interferometry scheme was refined through multiple campaigns to investigate the effects of p...We present an interferometry setup and the detailed fringe analysis method for intense short pulse(SP) laser experiments.The interferometry scheme was refined through multiple campaigns to investigate the effects of pre-plasmas on energetic electrons at the Jupiter Laser Facility at Lawrence Livermore National Laboratory. The interferometer used a frequency doubled(λ=0.527 μm) 0.5 ps long optical probe beam to measure the pre-plasma density, an invaluable parameter to better understand how varying pre-plasma conditions affect the characteristics of the energetic electrons. The hardware of the diagnostic, data analysis and example data are presented. The diagnostic setup and the analysis procedure can be employed for any other SP laser experiments and interferograms, respectively.展开更多
基金supported by JSPS KAKENHI(20H00125,21K20500,and 23H00273),Research Foundation for Opto-Science and Technology,Nakatani FoundationUTEC-UTokyo FSI Research Grant Program.
文摘Raman scattering spectroscopy is widely used as an analytical technique in various fields,but its measurement process tends to be slow due to the low scattering cross-section.In the last decade,various broadband coherent Raman scattering spectroscopy techniques have been developed to address this limitation,achieving a measurement rate of 500 kSpectra/s.Here,we present a substantially increased measurement rate of 50 MSpectra/s,which is 100 times higher than the previous state-of-the-art,by developing time-stretch coherent Raman scattering spectroscopy.Our newly developed system,based on a mode-locked Yb fiber laser,enables highly efficient broadband excitation of molecular vibrations via impulsive stimulated Raman scattering with an ultrashort femtosecond pulse and sensitive time-stretch detection with a picosecond probe pulse at a high repetition rate of the laser.As a proof-of-concept demonstration,we measure broadband coherent Stokes Raman scattering spectra of organic compounds covering the molecular fingerprint region from 200 to 1,200 cm^(-1).This high-speed broadband vibrational spectroscopy technique holds promise for unprecedented measurements of sub-microsecond dynamics of irreversible phenomena and extremely high-throughput measurements.
基金support from the LDRD (15-ERD-054) program to finish the manuscriptthe auspices of the US DOE by LLNL under contract no.DEAC52-07NA27344funded by the LDRD (12-ERD-062) program
文摘We present an interferometry setup and the detailed fringe analysis method for intense short pulse(SP) laser experiments.The interferometry scheme was refined through multiple campaigns to investigate the effects of pre-plasmas on energetic electrons at the Jupiter Laser Facility at Lawrence Livermore National Laboratory. The interferometer used a frequency doubled(λ=0.527 μm) 0.5 ps long optical probe beam to measure the pre-plasma density, an invaluable parameter to better understand how varying pre-plasma conditions affect the characteristics of the energetic electrons. The hardware of the diagnostic, data analysis and example data are presented. The diagnostic setup and the analysis procedure can be employed for any other SP laser experiments and interferograms, respectively.
