Strong Kα Emission in Picosecond Laser-Plasma Interactions

Abstract

Kα emission is observed from the interaction of a picosecond, 1.05-μm laser pulse at 4 × 1015 W/cm2 with a silicon target coated with various thicknesses of aluminum. Strong Kα emission requires a p-polarized, high-intensity-contrast laser pulse. At 7.1 Å, the Kα yield is 1.5 × 108 photon/sr with a duration of emission of ~8 ps and a source area of 1.6 × 10‒6 cm2. The radiance is ~3 × 109 W/cm2 sr. Monte-Carlo simulations have suggested that under these conditions Kα emission is a promising candidate to obtain an efficient, ultrashort x-ray source at ~1.5 Å.