Effect of double pulse laser irradiation on the dynamics of picosecond laser-produced plasma

Abstract

Measurements to control the morphology and characteristics of a picosecond laser produced chromium plasma plume upon double-pulse (DP) irradiation are presented and compared to their single-pulse (SP) counterpart. DP schemes are implemented by employing two geometries where the inter-pulse delay and the spatial separation are the control parameters. The ratio of plume length to plume width decreases upon increasing the inter-pulse delay and/or the energy of the second pulse in the collinear DP scheme. Interestingly, plasmas generated in the DP scheme at lower pressures resemble the expansion features of the plasma generated in the SP scheme at higher pressures. We find that DP schemes are advantageous for applications such as high harmonic generation and the production of quality thin films.