Frequency pulling by hyperfine σ transitions in cesium beam atomic frequency standards

Abstract

It is demonstrated that frequency pulling by Δm=±1 hyperfine σ transitions, here called Ramsey pulling, is a real calculable effect in atomic beam frequency standards. An analytic expression for the effects of Ramsey pulling is derived using perturbative techniques for the driving σ transitions, while treating the primary π transitions exactly. It is shown that these Ramsey pulling effects are intrinsically different from Rabi pulling in origin, manifestation, and elimination. These predictions are compared to measurements performed on a cesium beam atomic frequency standard, giving good quantitative verification of the theory and a clear demonstration of the existence of these effects.