Numerical Modeling of High Intensity Laser-Solid Interactions at 400 nm*

High order harmonic generation from laser solid-density plasma interactions can produce attosecond pulse trains of x-rays, which possess a broad range of applications in fundamental science, medicine, and industry. Particle-In-Cell (PIC) simulations were used to model the interaction between high-contrast, relativistically intense laser pulses and solid-density targets at oblique incidence angles.The simulations implemented laser parameters modeled after the ALEPH laser system, enabling femtosecond pulse duration, high intensities (10¹⁸ - 10²¹ W/cm²),  at a wavelength of 400 nm. Mechanisms of attosecond pulse generation were identified, including Relativistic Oscillating Mirror (ROM) and Coherent Wake Emission (CWE).