Detuning-induced stimulated Raman adiabatic passage in atoms with hyperfine structure

Abstract

We theoretically study the generation of coherence in generalized two-level atoms with hyperfine structure by utilizing the detuning-induced stimulated Raman adiabatic passage (D-STIRAP). As expected, the degree of attainable coherence between the ground and excited states cannot be as large as that for the ideal two-level atoms without hyperfine structure. However, we find that the substantial degree of coherence can still be produced with small modulations, and the modulation period is essentially determined by the hyperfine splittings in the ground and excited states. The D-STIRAP scheme in generalized two-level atoms is sufficiently robust against the various parameters such as intensities of lasers, initial detuning, time delay between the laser pulses, and Doppler broadening. As a specific example, we show realistic results for the D 1 transition of Na.

Stable quantum interference enabled by coexisting detuned and resonant STIRAPs*

“…[23] Unfortunately, only (two-photon) resonant-STIRAP (or R-STIRAP) is favored by previous studies owing to the existence of an absolute dark eigenstate which is totally isolated from the influences of other bright eigenstates. [24] In contrast, detuned-STIRAP (or D-STIRAP) enabled by other nearby energy levels is usually ignored [25,26] because of the coexisting R-STIRAP making its impact less important. The achievement of the STIRAP-induced quantum interference effect unexpectedly reveals the virtue of D-STIRAP even if the resonant transfer is active, which can provide an accurate measurement for the tiny energy difference between hyperfine ground states.…”