摘要
We report on an experimental investigation on the dynamic decoherence process of molecular rotational wavepackets during femtosecond laser filamentation based on time-dependent mean wavelength shifts of a weak probe pulse. Details of periodic revival structures of transient alignment can be readily obtained from the measured shifted spectra due to the periodic modulation of the molecular refractive index. Using the method, we measured decoherence lifetimes of molecular rotational wavepackets in N2and O2under different experimental conditions. Our results indicate that decoherence lifetimes of molecular rotational wavepackets are primarily determined by the relative population of rotational states in the wave packet and intermolecular collisions,rather than the focusing intensity.
We report on an experimental investigation on the dynamic decoherence process of molecular rotational wavepackets during femtosecond laser filamentation based on time-dependent mean wavelength shifts of a weak probe pulse. Details of periodic revival structures of transient alignment can be readily obtained from the measured shifted spectra due to the periodic modulation of the molecular refractive index. Using the method, we measured decoherence lifetimes of molecular rotational wavepackets in N_2 and O_2 under different experimental conditions. Our results indicate that decoherence lifetimes of molecular rotational wavepackets are primarily determined by the relative population of rotational states in the wave packet and intermolecular collisions,rather than the focusing intensity.
基金
supported by the National Basic Research Program of China(No.2014CB921303)
the National Natural Science Foundation of China(Nos.61575211,11674340,61405220,11404357,61605227,61705034,and 11704066)
the Strategic Priority Research Program of Chinese Academy of Sciences(No.XDB16000000)
the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(No.QYZDJ-SSW-SLH010)
the Shanghai Yangfan Program(No.16YF1412700)
the Natural Science Foundation of Jiangxi Province(No.20171BAB211007)
the Science and Technology Project of Jiangxi Provincial Education Department(Nos.GJJ160587 and GJJ160576)
the Shanghai Rising-Star Program(No.17QA1404600)
