Polarization dragging in degenerated four-wave mixing (A)

V. J. Sánchez-Morcillo, Germán J. de Valcárcel, Eugenio Roldán

Hai Wang

The impact of the pump polarization during the Rb atom degenerate four-wave mixing process on the degenerate four-wave mixing signals is studied.In the experiment,a pump light and the probe light transmitted in the same direction into the air chamber Rb atoms,and the other pump light propagated through the atoms in the opposite direction.Then,by changing the polarization of the two pump lights,the four-wave mixing signal is observed.The result shows that when the two pump light polarization is parallel,a strong four-wave mixing signal can be observed.While the two pump light polarization is orthogonal to each other,the four-wave mixing signal disappear.The theoretical analysis indicates that the population grating induced by the pump beam interference is the physics mechanism of the degenerate four-wave mixing signal.

Xuemei Cheng, Yigang Du, Yanpeng Zhang +4 more

Jiaqi Yuan, Xuemei Cheng, Xing Wang +2 more

We report on a new method to achieve the single-scan polarization-resolved degenerate four-wave mixing (DFWM) spectroscopy in a Rb atomic medium using a vector optical field, in which two pump beams are kept linearly polarized and a vector beam is employed as the probe beam. As the polarization and intensity of the DFWM signal are closely dependent on the polarization state of the probe beam, a vector probe beam with space-variant states of polarization is able to generate a DFWM signal with space-variant states of polarization and intensity across the DFWM image. Accordingly, the polarization-resolved spectra can be retrieved from a single DFWM image. To the best of our knowledge, this is the first time that the single-scan polarization-resolved spectrum detection has been realized experimentally with a vector beam. This work provides a simple but efficient single-scan polarization-resolved spectroscopic method, which would be of great utility for the samples of poor light stability and fast optical processes.

A. Lezama, George C. Cardoso, J. W. R. Tabosa

Nearly degenerate four-wave mixing (NDFWM) within a closed degenerate two-level atomic transition is theoretically and experimentally examined. Using the model presented by Lezama et al. [Phys. Rev. A 61, 013801 (2000)] the NDFWM spectra corresponding to different pump and probe polarization cases are calculated and discussed. The calculated spectra are compared to the observation of NDFWM within the ${6S}_{1/2}(F=4)\ensuremath{\rightarrow}{6P}_{3/2}(F=5)$ transition of cesium in a phase conjugation experiment using magneto-optically cooled atoms.

Kaige Wang, Luigi Lugiato, Neal Broadus Abraham