The development of a hydrodynamic instability in laser targets is studied by means of a 2-D numerical code “ATLANT”. During the linear stage, the perturbations grow as:
In the nonlinear stage the growth rate of the Rayleigh-Taylor instability is reduced, and new harmonics are generated. The effect of the nonuniformity of the laser irradiation has been investigated for long-wave and short-wave perturbations. The growth rate of short-wave perturbations may be effectively decreased by means of symmetrical pre-pulses.