SEMICLASSICAL INITIAL-VALUE APPROACH FOR CHAOTIC LONG-LIVED DYNAMICS

A time-dependent initial value semiclassical propagator approach is de veloped and applied to the propagation of a two-dimensional quantum sy stem whose classical counterpart is highly chaotic. The energy spectru m of a quartic oscillator, obtained from the propagated wavefunction, is shown to be accurately and simply computed by application of statio nary-phase Monte Carlo integration. Chaotic trajectories are handled n aturally, without giving rise to the singularities seen in other metho ds. (C) 1998 American Institute of Physics. [S0021-9606(98)00932-5].