We report the examination of the dynamics of dissociative tunnel ionization of ${\mathrm{H}}_2$ in a 10-μm laser field. The kinetic energy of the dissociated fragments along with ion yields were measured. The proposed model prediction agrees with the observed intensity dependencies, suggesting the dynamics of the process: the tunnel ionization of ${\mathrm{H}}_2$ is followed by the chaotic dissociation of ${\mathrm{H}}_2^{+}$ in the beyond-dissociation threshold field, and the process is completed by the associative tunnel ionization of the neutral fragments.

• Received 28 November 1994

DOI:https://doi.org/10.1103/PhysRevA.51.R2695