Study On Supercontinuum Spectrum In Some Solutions By Femtosecond Laser

In recent years, the rapid development of the intense ultrashort pulse laser technology gives a lot of new contents on the interaction of light and matter. Among them, a new physical phenomenon is the femtosecond laser nonlinear propagation in a transparent medium with the formation of plasma filaments. Associated with the nonlinear propagation of femtosecond laser, supercontinuum radiation generates in the direction along the laser transmission. First of all, we give the short description about the femtosecond transmitting in the transparent medium and the basic definition of plasma filaments. The development and some typical application of the research is reviewed. On the second part, several major impact mechanism are introduced, such as self-phase modulation, multiphoton ionization, plasma defocusing and intensity clamping, and the phenomenon accompanied with filamentation is illustrated. On the part of experiment, The supercontinuum spectrum from alcohol, distilled water, solution of KMnO4and CUSO4are studied. By comparing the data, the CUSO4solution is chosen. The experimental conditions about input energy, solution concentration, solution temperature, focusing position, focusing lens and polarization state are changed. The effect of various parameters is investigated.