  Intense laser technologies generate light with unprecedented and growing
intensities. The possibility emerges that a nucleus responds nonlinearly to an
intense light field, pointing to a yet little explored research area of nuclear
nonlinear optics. We consider two-photon and three-photon absorption (with
subsequent disintegration) processes of the deuteron, the simplest and the most
fundamental nontrivial nucleus, as prototypes of nuclear nonlinear optical
effects. Quantitative calculations are performed on these processes and novel
observable effects are predicted.
