The creation of carbonaceous nanoparticles and their dynamics in hydrocarbon flames are still debated in environmental,combustion,and material sciences.In this study,we introduce single-pulse femtosecond laser sheetco...The creation of carbonaceous nanoparticles and their dynamics in hydrocarbon flames are still debated in environmental,combustion,and material sciences.In this study,we introduce single-pulse femtosecond laser sheetcompressed ultrafast photography(fsLS-CUP),an ultrafast imaging technique specifically designed to shed light on and capture ultrafast dynamics stemming from interactions between femtosecond lasers and nanoparticles in flames in a single-shot.fsLS-CUP enables the first-time real-time billion frames-per-second(Gfps)simultaneous twodimensional(2D)imaging of laser-induced fluorescence(LIF)and laser-induced heating(LIH)that are originated from polycyclic aromatic hydrocarbons(PAHs)and soot particles,respectively.Furthermore,fsLS-CUP provides the real-time spatiotemporal map of femtosecond laser-soot interaction as elastic light scattering(ELS)at an astonishing 250 Gfps.In contrast to existing single-shot ultrafast imaging approaches,which are limited to millions of frames per second only and require multiple laser pulses,our method employs only a single pulse and captures the entire dynamics of laserinduced signals at hundreds of Gfps.Using a single pulse does not change the optical properties of nanoparticles for a following pulse,thus allowing reliable spatiotemporal mapping.Moreover,we found that particle inception and growth are derived from precursors.In essence,as an imaging modality,fsLS-CUP offers ultrafast 2D diagnostics,contributing to the fundamental understanding of nanoparticle’s inception and broader applications across different fields,such as material science and biomedical engineering.展开更多
基金the Swedish Research Council for the financial support of grant#IPD2018-06783Part of the work of Y.N.M.that was enabled by JPL was carried out at the Jet Propulsion Laboratory,California Institute of Technology,under a contract with NASA(80NM0018D0004)MSG thanks funding from JPL JROC and NASA SSW programs.
文摘The creation of carbonaceous nanoparticles and their dynamics in hydrocarbon flames are still debated in environmental,combustion,and material sciences.In this study,we introduce single-pulse femtosecond laser sheetcompressed ultrafast photography(fsLS-CUP),an ultrafast imaging technique specifically designed to shed light on and capture ultrafast dynamics stemming from interactions between femtosecond lasers and nanoparticles in flames in a single-shot.fsLS-CUP enables the first-time real-time billion frames-per-second(Gfps)simultaneous twodimensional(2D)imaging of laser-induced fluorescence(LIF)and laser-induced heating(LIH)that are originated from polycyclic aromatic hydrocarbons(PAHs)and soot particles,respectively.Furthermore,fsLS-CUP provides the real-time spatiotemporal map of femtosecond laser-soot interaction as elastic light scattering(ELS)at an astonishing 250 Gfps.In contrast to existing single-shot ultrafast imaging approaches,which are limited to millions of frames per second only and require multiple laser pulses,our method employs only a single pulse and captures the entire dynamics of laserinduced signals at hundreds of Gfps.Using a single pulse does not change the optical properties of nanoparticles for a following pulse,thus allowing reliable spatiotemporal mapping.Moreover,we found that particle inception and growth are derived from precursors.In essence,as an imaging modality,fsLS-CUP offers ultrafast 2D diagnostics,contributing to the fundamental understanding of nanoparticle’s inception and broader applications across different fields,such as material science and biomedical engineering.