Source of metastable H(2s) atoms using the Stark chirped rapid-adiabatic-passage technique

We propose the use of Stark chirped rapid-adiabatic-passage method, a techn ique in which the energy of a target state is swept through resonance by a slowly varying dynamic Stark shift to induce complete population transfer f rom the ground 1s state to the metastable 2s state of the hydrogen atom. Pa rasitic ionization processes are strongly reduced by using a two-color exci tation scheme. Our detailed numerical calculations show that under judiciou s choice of pulse parameters, up to 98% of the population can be found in t he 2s state at the end of the process. [S1050-2947(99)51112-8].