Doppler effects in a multi-wavelength Rabi cavity for the excitation of atomic beams in microwave frequency standards

An analysis is presented of the feasibility of using a single, multiwavelength Rabi cavity for high-resolution, accurate interrogation of an atomic beam in frequency standard applications. Reasons for interest in this solution are mainly the compactness and the ease of construction that such a cavity would offer, but major questions must first be answered on the expected magnitude of Doppler related effects before a resonator of this kind can be seriously considered. An analytical approach and numerical calculations are given to show that the problem may not be as severe as one might think. In particular, it seems that a cylindrical cavity in the high-intrinsic-Q TE₀₁ mode would be capable of compensating Doppler effects to a very high degree