Line shape and light shift of coherent population trapping resonance under Ramsey interrogation in ‘hot’ atoms in an optically dense medium

Abstract

A theory is developed for the effect of coherent population trapping (CPT) in 'hot' atoms under pulsed pumping in an optically dense medium with a buffer gas. The case is considered when the excited level is not degenerate. Based on an analysis of the shape of Ramsey resonances, we show that with increasing optical density of the medium, the dependence of the light shifts of the CPT resonance becomes more and more nontrivial. The dependence of the light shifts of the CPT resonance on the magnitude of the hyperfine splitting of the excited level, concentration of active atoms, temperature, and duration of the dark pause is constructed.

Influence of collisions on the effect of electromagnetic-induced transparency in cells of finite sizes with anti-relaxation coating of walls

“…The type of this function is determined by the boundary conditions. The susceptibility of a unit of the phase volume of the medium to the test field, exclusive of the possible incoherent scattering [80][81][82][83], is calculated by means of optical coherence (8) and (9) (see, for instance, [71]) as…”

“…Let us compare the spectral dependences of the contrast of the transparency resonances calculated using ( 16) and (15) with the corresponding numerical calculation performed in [71]. The resonance contrast is defined as C( p ) = 1 − χ"( p )/χ" 0 , where χ"( p ) and χ" 0absorption coefficients at a given detuning and in the absence of transparency resonance, respectively.…”

“…At the same time, it is well known that taking into account the real atomic structure leads to qualitative features that do not allow description by means of a simple three-level model [68]. So, in the case of CPC, it turns out [69][70][71] that taking into account already one additional excited state in the theoretical description leads to significant differences from the predictions obtained when describing such phenomena in the framework of a threelevel lambda model.…”