Dynamics of cooperative emissions in a cascade three-level molecular system driven by an ultrashort laser pulse  

作　　者：刘纪彩 王春兴 Gel’mukhanov Faris 王传奎 

机构地区：[1]College of Physics and Electronics, Shandong Normal University, Jinan 250014, China [2]Department of Theoretical Chemistry, School of Biotechnology, Royal Institute of Technology, SE-10691 Stockholm, Sweden

出　　处：《Chinese Physics B》2008年第11期4211-4217,共7页中国物理B（英文版）

基　　金：Project supported by National Basic Research Program for China (Grant No 2006CB806000);Swedish Research Council, Carl Tryggers Stiftelse Foundation, Swedish International Development Cooperation Agency (SIDA);Natural Science Foundation of Shandong Province of China (Grant No Z2007A02)

摘　　要：This paper investigates the dynamics of cooperative emissions in a cascade three-level system driven by an ultra, short laser pulse by solving numerically the full-wave Maxwell-Bloch equations. The 4, 4＇-bis（dimethylamino） stilbene molecule is used as the model molecule because of its strong two-photon absorption property. The two-colour cooperative emissions are studied as functions of molecular number density and dephasing rate of the dipole coherence. The propagation effects on the evolution of the cooperative radiations are also taken into account. The cooperative radiations are enhanced for large number density of the molecule, while the fast dephasing of the dipole coherence reduces the intensity of the cooperative radiations and delays the emission times or even inhibits the formation of the emissions. The delay time of the radiation decreases with the increase of the molecular number density and the propagation distance.This paper investigates the dynamics of cooperative emissions in a cascade three-level system driven by an ultra, short laser pulse by solving numerically the full-wave Maxwell-Bloch equations. The 4, 4＇-bis（dimethylamino） stilbene molecule is used as the model molecule because of its strong two-photon absorption property. The two-colour cooperative emissions are studied as functions of molecular number density and dephasing rate of the dipole coherence. The propagation effects on the evolution of the cooperative radiations are also taken into account. The cooperative radiations are enhanced for large number density of the molecule, while the fast dephasing of the dipole coherence reduces the intensity of the cooperative radiations and delays the emission times or even inhibits the formation of the emissions. The delay time of the radiation decreases with the increase of the molecular number density and the propagation distance.

关 键 词：SUPERFLUORESCENCE ultra-short laser pulse 4 4＇-bis（dimethylamino） stilbene organic molecule Maxwell-Bloch equations 

分 类 号：TN24[电子电信—物理电子学] O561[理学—原子与分子物理]