Abstract

We investigate the onset of chaos in a system composed of an ionic molecule driven by a laser pulse whose frequency is nearly resonant with molecular vibrations. The continuous radiation spectrum generated by the molecule is shown to be of two different origins. For low intensity chirped lasers, the continuum is the result of a large number of discrete transitions between energy levels of the excited molecule. For unchirped and chirped lasers at higher intensities, the continuum is produced by chaotic motion of the molecule. This is evidenced by a sudden increase in the system’s dimensionality and the transition of the system’s largest Lyapunov exponent from negative to positive.

© 1993 Optical Society of America