Filament Fluorescence Mechanism Of Gas Phase Molecules In Strong Femtosecond Laser Field

The light produced by the amplification of the stimulated radiation is called a laser,with the development of laser technology,in recent years,femtosecond laser has gradually entered our field of vision,With the advent of femtosecond laser,the interaction between light and matter has entered a strong interaction Era.With the increase of laser intensity,laser and molecular atoms have different effects,Molecular orientation,ionization and dissociation,Kulun explosion,nuclear fission,nuclear fusion phenomenon which appeared in succession,the phenomenon is not only for us to study the structures and properties of molecules and atoms provide a strong basis,but also to promote the development of femtosecond laser technology.At the same time,the propagation of femtosecond laser pulses in air is also the focus of researchers,when the femtosecond laser propagation in the air,creating a dynamic balance between femtosecond laser beam and plasma generated,this balance is caused by defocusing optical Kerr effect and plasma,so you can see a light wire in the air,the femtosecond laser filamentation.Because this kind of light can spread far away,it can be applied in practice.The main contents of this thesis include the following parts:The first part is the introduction of laser and femtosecond laser characteristics and applications.With the rapid development of science and technology,in recent years,the pulse of the laser has become shorter and shorter,from the previous picosecond to the present even femtosecond laser,the laser has contributed to more areas,and the laser has a good monochromatic,directional,coherence and high brightness,so the role of the laser is reflected in all aspects,such as industrial,medical,commercial,scientific research,information and military applications.The second part introduces the problems related theory of laser filamentation and research process and solutions.Study on laser filamentation problem,the researchers found a lot of laser filamentation positive and good for its use,its application to many aspects,but there are also some problems,better able to avoid these problems is very important.The third part introduces the experiment device.The fourth part is the main part of the paper,femtosecond CO₂ molecules in strong fields are introduced into silk fluorescence kinetics.In different polarization,air pressure,fluorescence spectrum into silk location detection into silk,analyzed the carbon dioxide in strong laser field into silk dynamics and fluorescence decay dynamics process.The fifth part of thesis mainly introduces the femtosecond N₂ molecules in strong fields into silk fluorescence kinetics several time scales.In the same molecule,seen from picosecond and nanosecond,subtle,and the fluorescence spectrum under the millisecond timescale,various time scales of molecular dynamics problem some are clear,some are to be solved,such as subtle under the orders of magnitude spectrum.