During the last 20 years my work has spanned a broad area in the interaction of radiation with atoms and molecules. One of the main and continuously sustained activities has been devoted to the theory of multiphoton interactions of lasers with atoms. It has led to the development of sophisticated techniques for the calculation of atomic structure in complex atoms, as well as the time-dependent dynamics. It has addressed problems in the perturbative as well as the non-perturbative regime, which at the present time represents one of the most challenging problems of the field, namely the behavior of complex atoms under superstrong, extremely short laser pulses for which even basic notions such as transition probability per unit time are inapplicable.
The theoretical tools developed in this endeavor have enabled my group to tackle problems in a variety of other subfields in Quantum Optics, Non-linear Optics, Atomic Laser Spectroscopy and Coherent Atom-Radiation Interactions. This has involved the study of the stochastic properties of radiation and its effects on the non-linear processes in all of the above topics. Most recently many of these phenomena have conspired to create challenging problems in the interaction of the atomic continuum with discrete states. Issues of localization and stabilization of decaying states acquire new significance under the interaction of atoms with strong coherent radiation. In addition to their fundamental significance, some of these problems bear strong connections with the quest for the creation of strong X-ray-sources, sensitive detection of single atoms in complex environments, plasma diagnostics, etc. Most recently, my interestes have expanded into the areas of Bose-Eistein condensation with emphasis on the atom laser, as well as into aspects of quantum information with emphasis on physical implementations.
During the period 1967-1971, the thrust of my work was on the theory of neutron-nuclear reactions, neutron transport theory and variational techniques for non-self adjoint problems with applications to reactor analysis.