Diagnostics of ionization front and plasma within femtosecond laser interferometer

Based on analyzing the condition of transmission through high density plasma and its ionization front, and the theory of detecting plasma with holographic interferometer, diagnostic experiments of ionization front and plasma ionized by high laser electric field has been reported in this paper. The Mach-Zehnder interferometer with the femosecond laser of center wavelength of 800nm and pulse duration of 58fs has been used to get interference images in CCD camera. By Abel inversion, the density map of plasma has been obtained based on the interference image. Evolution pictures of ionization front within the time or propagation distance have been reported and ionization front’s size has been estimated with the help of 4mm diameter of nozzle. One good diagnosis method for ionization front and plasma has been given within these experiments.