FROM FILAMENTATION IN CONDENSED MEDIA TO FILAMENTATION IN GASES

We demonstrated how the moving focus model developed for condensed med ia should be modified for the explanation of experiments on filamentat ion of high-power femtosecond laser pulses in air. This modification i s based on the consideration of gas ionization in high-intensity laser field. Numerical simulations based on this modified model allow for t he explanation not only of filamentation itself but also the accompany ing phenomena such as refocusing and conical emission.