We successfully observed the nonlinear eight-wave mixing (EWM) signal via one electromagnetically induced transparency (EIT) window and double optical pumping channels in an open five-level atomic system of 87 Rb. By carefully controlling the arrangement of the incident laser beams, the corresponding four-wave mixing (FWM), six-wave mixing (SWM) and EWM signals can be made to coexist with similar signal amplitudes and transmit through the same EIT window in such open five-level atomic system.
We experimentally report on the evolution from singly-dressed to doubly-dressed four-wave mixing (FWM) process by controlling the powers of the probe, the pump and the dressing fields respectively. The differences in the enhancement and the suppression of FWM signal between the two-level and cascade three-level atomic systems are observed and explained by the multi-dressed effect theoretically. Both the x direction and the y direction spatial splittings of the degenerate-FWM (DWFM) beams are obtained. We also investigate the switch between the enhancement and the suppression of the DWFM signals and between its spatial splittings in x direction and y direction. The spatial splittings in x direction and y direction can be controlled by the relative position and the intensity of the involved laser beams. Such a study can be useful for optimizing the efficiency of the FWM process and providing potential applications in spatial signal processing.
We experimentally investigate the interplay between two coexisting six-wave mixing (SWM) signals and the interference between coexisting four-wave mixing (FWM) and SWM signals in a five-level atomic system of 85 Rb. When two electromagnetically induced transparency windows gradually overlap in frequency, the competition between these two SWM signals arises. Moreover, we report the experimental result which shows that the temporal interference with femtosecond time scales between FWM and SWM signals.
Based on double optical pumping channels, we experimentally study the competition between two coexistent six-wave mixing (SWM) processes falling into two electromagnetically induced transparency windows by scanning the frequency of the probe field in two similar five-level atomic systems of 85 Rb. By blocking one optical pumping channel unrelated to the four-wave mixing (FWM) process, one SWM process, together with the FWM process, generated by a conjugated small-angle static grating could be observed in the spectrum. Moreover, the other SWM process obtained by blocking the first SWM channel is also observed together with the FWM process in a lower N-type four-level subsystem. These experimental results agree well with theoretical predictions.OCIS codes: 190.4180, 270.1670, 190.4223. doi: 10.3788/COL201109.121902. Electromagnetically induced transparency (EIT) has been studied well in the last two decades [1] . Because the generated signals can be transmitted through the resonant atomic medium with little absorption under the EIT condition, multiwave mixing (MWM) [2−4] processes can be investigated. Using one EIT window, the generated four-wave mixing (FWM) and six-wave mixing (SWM) signals are able to coexist in an open-cycle atomic system. Moreover, the competition and interference [5,6] between these FWM and SWM processes have been studied via atomic coherence in a four-level atomic system.In Fig. 1(a1), the weak probe field E 1 (with tunable frequency ω 1 , wave vector k 1 , and Rabi frequency G 1 ) drives the transition from |0 to |1 with resonant wavelength of 780.245 nm. The frequency detuning is ∆ 1 . The coupling field E 2 (ω 2 , k 2 , ∆ 2 , and G 2 ) drives the transition between |1 -|2 with the resonant wavelength of 775.978 nm; two pump beams, E 3 (ω 3 , k 3 , ∆ 3 , and G 3 ) and E 3 (ω 3 , k 3 , ∆ 3 , and G 3 ), from the same laser drive the transition between |3 -|4 with the resonant wavelength of 780.234 nm, and another pump beam E 4 (ω 4 , k 4 , ∆ 4 , and G 4 ) drives the transition between |1 -|4 with the resonant wavelength of 780.235 nm. Using four external cavity diode lasers (ECDL) with line width less than or equal to 1 MHz, these relevant transitions can be effectively driven in 85 Rb atoms system. The powers of beams, E 1 , E 2 , E 3 , E 3 , and E 4 , are 3.7, 50, 20, 20, and 48 mW, respectively. Laser beams E 2 , E 3 , and E 3 propagate in the same direction with small angles of ∼ 0.3• and overlap at one spot inside a rubidium atom vapor cell of 7.5-cm length. A typical atomic density in the cell is 2 × 10 11 cm −3 . The probe beam E 1 and pump beam E 4 propagate in the same direction ( Fig. 1(b)).According to the phase-matching conditions, one FWM and two SWM processes can be generated simultaneously in the same direction. Firstly, by blocking the coupling beams E 2 and E 4 , the FWM process with the phasematching condition k f = k 1 + k 3 − k 3 can be regarded as a scattering of the probe field E 1 over the smallangle static grating formed by the conjugate field pair of E 3 and E ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.