Numerical analysis of non-collinear coherently combined laser beams interaction with micro-structured targets

Abstract

In this work, we numerically investigate the laser beam intensification in a non-collinear coherently combined (NCCC) laser beams–micro-structured target interaction system, in the presence of pulse duration variation, down to few-cycle regime. A 2D numerical model based on finite-difference time domain (FDTD) method is performed in order to provide a spatio-temporal description of the electromagnetic field distribution in the vicinity of the laser–target interaction point in case of NCCC of multiple laser pulses. The results demonstrate that non-collinear coherent and spectral beam combination of three laser pulses in a micro-structured cone target allow a significant increase of the field intensity while a reduction of temporal duration of the combined pulse occurs. This numerical model offers an effective solution to increase the laser intensity in a micro-structured cone target by employing coherent and spectral beam combination of multiple laser sources and it can be used as an alternative method for field intensity enhancement in various laser–matter interaction experiments in ultra-intense regime.