Decay and modulation instabilities of beat waves in a plasma

Summary A large-amplitude beat wave excited at the beat frequency of two copropagating laser beams is extremely unstable and suffers strong three- and fourwave parametric instabilities with large growth rates. The relativistic effects are seen to be negligible on both the decay and modulation instabilities. However, the growth rates of these instabilities are sensitive functions of the plasma parameters. The authors of this paper have agreed to not receive the proofs for correction.