Rabi and Ramsey interrogations of metastable beams

Abstract

The interaction between a metastable atomic beam and a standing-wave radiation field is analyzed taking into account the effects of the natural decay between the interrogation zones and in the detection region; moreover the problem is concerned with atomic beams with cross section much wider than the radiation wavelength (multiwavelength cross section). The analysis is carried out in the density matrix formalism and numerical results obtained refer to the new frequency standards based on fine structure transitions within the Mg and Ca metastable triplets.

Rabi and Ramsey techniques have been considered and the interesting figures of signal-to-background and signal-to-noise ratios, linewidth and saturation field have been evaluated assuming a Maxwellian velocity distribution and taking into account the detection process.