Dissociation quenching using exceptional points.

We examine a short way to reach an exceptional point that corresponds to a coalescence of two resonance energies. The application concerns the photodissociation of the Na2 molecule exposed to a laser field. In this case, the resonances can be correlated with the field-free vibrational states of the diatomic species. The resonances are due to the field-induced coupling with the continuum of a repulsive potential. We also draw attention to a new kind of exceptional point involving a resonance originating from a vibrational state coalescing with a shape-type resonance of the repulsive potential. A laser control scenario, aiming at the adiabatic transport from this field-free decaying state to a stable field-free vibrational state, is discussed in terms of field-induced dissociation quenching.