Observation of the fluorescence spectrum for a driven cascade model system in atomic beam

Abstract

We experimentally study the resonance fluorescence from an excited two-level atom when the atomic upper level is coupled by a nonresonant field to a higher-lying state in a rubidium atomic beam. The heights, widths and positions of the fluorescence peaks can be controlled by modifying the detuning of the auxiliary field. We explain the observed spectrum with the transition properties of the dressed states generated by the coupling of the two laser fields. We also attribute the line narrowing to the effects of Spontaneously Generated Coherence between the close-lying levels in the dressed state picture generated by the auxiliary field. And the corresponding spectrum can be viewed as the evidence of Spontaneously Generated Coherence. The experimental results agree well with calculations based on the density-matrix equations.

Controllable cavity linewidth narrowing via spontaneously generated coherence in a four level atomic system

“…When an atom is coupled to the modified vacuum [38][39][40][41], quantum interference occurs even if the corresponding dipole moments are orthogonal. And SGC can also be simulated by additional fields in the dressedstate picture [42][43][44][45][46][47][48]. Moreover, the tunneling effect in quantum wells and quantum dots can also lead to quantum interference [49][50][51][52].…”

“…And SGC can also be simulated in the dressed atoms interacting with a dc field [42], microwave field [43,44] or laser field [45]. And most recently, by the coherent laser fields we experimentally observed SGC on absorption and fluorescence in rubidium atomic beam [46][47][48]. Besides, in quantum wells and quantum dots, the tunneling effect can also lead to quantum interference [49][50][51][52].…”

Effects of spontaneously generated coherence on resonance fluorescence from triple quantum dot molecules

“…[15] and [21], we calculate the steady-state fluorescence spectrum. As is well known, the fluorescence spectrum is proportional to the …”

“…The resonance fluorescence spectrum of multiple-level system driven by two or more lasers has much more structure and shows a variety of interesting effects, duo to the more complex internal dynamics of the system. And most recently, we have experimentally observed the resonance fluorescence spectrum for a driven cascade model system in the atomic beam [15].…”

Controlling the spontaneous emission of a quantum emitter in an elliptically polarized field

“…In addition, inhibition and enhancement of the spontaneous emission of quantum dots (QDs) can be realized in laterally structured microresonators [16]. Tian et al [17] have proposed an experimental scheme to observe the resonance fluorescence from an excited atomic system; the results show that the positions, heights, and linewidths of the fluorescence peaks can be controlled by tuning the detuning of the auxiliary field. Furthermore, the effective control of spontaneous emission plays a critical role in designing various optical elements and devices, such as single photon source [18,19], quantum information processing [20][21][22], semiconductor laser [23], solar cells [24], and so on.…”