Schrodinger-like equations play an essential role in the modeling of plasma
s created by laser beams, and taking into account of relativistic terms yie
lds anew kind of nonlinearity in them, as compared to the classical case. A
numerical scheme involving a new handling of absorbing conditions suitable
for Schrodinger-like equations is given, and several general models are st
udied: the classical cubic case linked to the Kerr effect for an anharmonic
plasma, where numerical experiments prove the efficiency of our code appli
ed to the computation of solitons and explosive solutions. Furthermore, new
kinds of explosive solutions are computed, and we numerically show the ess
ential role of the ground state to get approximations of the cubic explosiv
e solution by global ones. A multiphotonic ionization model is also studied
including higher-order terms in the nonlinearity. In this case, we obtain
stable structures physically explained by competing saturation processes. T
hese structures have been experimentally detected. Finally, a relativistic
model involving the Lorentz kinematic factor in the evolution equations is
investigated numerically; filamentary structures are found in agreement wit
h predicted relativistic phenomena. (C) 1999 John Wiley & Sons, Inc.