A bistable system with an electromagnetically induced grating

Controllable optical mirror of cesium atoms with four-wave mixing

“…χ (1) is the linear susceptibility of the probe light, and its real part corresponds to the dispersion of the probe, and expressed as [9] χ (1)…”

“…The detailed theoretical analysis can be found in Ref. [9]. Now we numarically caculate the values of reflection efficiency R as a function of probe detuning for Case A and Case B (see Fig.…”

“…[4] For a Λ-type three-level atomic system in hot atoms, the two-photon resonance for EIT needs to be Doppler-free, so that the traveling probe and coupling fields are co-propagating. When a standing-wave field formed by two counter-propagating fields was coupled to the Λtype three-level system, other than transparent, a strong linenarrowed absorption of the probe light occurred, [5,6] which effect was explained as electromagnetically induced grating (EIG) [7][8][9] or four-wave mixing (FWM), [10,11] and even more exhibits the effect similar to that of optical photonic crystal, resulting from spatial periodic modulation of absorptions and group velocities in cold atoms, [12] which leads to the reverse probe light. In hot atoms, because of the Doppler shift, the atoms 'see' the counterpropagating coupling fields as bichromatic fields rather than a chromatic standing wave (SW), therefore an moving optical photonic crystal effect was established in atoms, and the function of all-optical optical diode was thus obtained.…”

Laser-induced diffraction grating in asymmetric double quantum well nanostructure

“…EIG is originally proposed by Ling in a three-level Λ-type atoms [9], then it is exploited to implement the optical switching and routing [10], and the optical bistability [11]. It has extensively been studied in Ξ-type [12], tripod-type [13], N-type [14,15], Y-type [16] atomic systems.…”