Sub-picosecond chirped laser pulse-induced airflow and water condensation were investigated in a cloud chamber.The results indicate that the positively chirped sub-picosecond laser pulses generate a more uniform inten...Sub-picosecond chirped laser pulse-induced airflow and water condensation were investigated in a cloud chamber.The results indicate that the positively chirped sub-picosecond laser pulses generate a more uniform intensity distribution inside the plasma column, leading to a weaker airflow and an elliptic-shaped snow pile. The negatively chirped sub-picosecond laser pulses generate a spark-like intensity distribution inside the plasma column, which produces a wider range of airflow and a round snow pile. The amount of snow weight and the concentration of NO3-- are found to be dependent on the intensity distribution inside the plasma column. The visibly stronger plasma column generates much more snow and a higher concentration of NO3--. These experimental results provide a reference for sub-picosecond laser-induced water condensation in realistic atmospheric conditions.展开更多
We demonstrate a simple technique to filter out the continuum background in filament-induced remote breakdown spectroscopy.By inserting a polarizer before the detector,the continuum background was reduced by more than...We demonstrate a simple technique to filter out the continuum background in filament-induced remote breakdown spectroscopy.By inserting a polarizer before the detector,the continuum background was reduced by more than 42%in filament-induced breakdown spectroscopy at a distance of 3.8 m,while the fluorescence intensity of aluminum atomic lines remains constant.Supercontinuum through self-phase modulation during filamentation mainly contributes to the continuum background.The polarization-gated technique provides a simple way to remove the continuum background in filament-induced remote breakdown spectroscopy.展开更多
基金supported by the National Natural Science Foundation of China(Nos.11425418,61475167,11404354,and 61221064)the State Key Laboratory Program of the Chinese Ministry of Science and Technology
文摘Sub-picosecond chirped laser pulse-induced airflow and water condensation were investigated in a cloud chamber.The results indicate that the positively chirped sub-picosecond laser pulses generate a more uniform intensity distribution inside the plasma column, leading to a weaker airflow and an elliptic-shaped snow pile. The negatively chirped sub-picosecond laser pulses generate a spark-like intensity distribution inside the plasma column, which produces a wider range of airflow and a round snow pile. The amount of snow weight and the concentration of NO3-- are found to be dependent on the intensity distribution inside the plasma column. The visibly stronger plasma column generates much more snow and a higher concentration of NO3--. These experimental results provide a reference for sub-picosecond laser-induced water condensation in realistic atmospheric conditions.
基金supported in part by the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB16000000)the Key Project from Bureau of International Cooperation of Chinese Academy of Sciences(No.181231KYSB20160045)the 100Talents Program of Chinese Academy of Sciences
文摘We demonstrate a simple technique to filter out the continuum background in filament-induced remote breakdown spectroscopy.By inserting a polarizer before the detector,the continuum background was reduced by more than 42%in filament-induced breakdown spectroscopy at a distance of 3.8 m,while the fluorescence intensity of aluminum atomic lines remains constant.Supercontinuum through self-phase modulation during filamentation mainly contributes to the continuum background.The polarization-gated technique provides a simple way to remove the continuum background in filament-induced remote breakdown spectroscopy.
