Optical vortex array generation of intense high-order harmonics

An ultra-short and ultra-intense optical vortex array (OVA) is generated when two intense counter-propagating Laguerre-Gaussian (LG) pulses with p-polarization impinge on two solid thin targets. In this paper, we propose a method for generating an OVA of high intensity, short wavelength, and high-order mode. Three-dimensional (3D) particle-in-cell (PIC) simulation results demonstrated that the generated high-order vortex harmonics interfered with each other in the transmitted area. These interference patterns of the fundamental and high-order harmonics exhibit an OVA distribution. Furthermore, vortex oscillating mirror (VOM) and classic wave interference models are then used to explain the simulation results.