PROPAGATION OF A RELATIVISTIC ULTRASHORT LASER-PULSE IN A NEAR-CRITICAL-DENSITY PLASMA-LAYER

Two-dimensional characteristics of propagation of a relativistic ultra short laser pulse in a thin plasma layer with near-critical density ha ve been studied. Although the critical density increases due to the re lativistic effect, the incident laser pulse does not penetrate into ov erdense plasma because a high-density wall of electrons is generated i n front of the laser pulse. It was found that the thin plasma layer is useful for reducing the pulse length of the incident laser as a nonli near optical material. [S1063-651X(98)02110-2].