Two-Dimensional Simulations of Single-Frequency and Beat-Wave Laser-Plasma Heating

Finite-beam, two-dimensional particle simulations of single- and double-frequency laser-plasma heating are presented. In the single-frequency case, Raman backscatter and side scatter initially heat the plasma. Even in the absence of strong forward Raman scattering, strong subsequent electron heating is observed. When two collinear laser beams with $\Delta \omega ={\omega }_p$ are used, a coherent plasma wave heats the electrons to many megaelectronvolts. In the latter case, ion dynamics eventually disrupts the heating process.