Spatial mapping of the polarization-resolved spectrum based on vector-beam-assisted nondegenerate four-wave mixing

Abstract

The introduction of vector beams (VBs), with space-variant polarization, into the polarization-resolved spectrum, provides a convenient and rapid pathway for revealing micro-structure. Here, we realize the spatial mapping of the polarization-resolved spectrum based on VB-assisted nondegenerate four-wave mixing (FWM) in a diamond atomic system of 85Rb. The 780 nm radial VB and 776 nm linearly polarized Gaussian beam serve as the probe and pump beams in the FWM process, respectively. The generated 420 nm coherent blue light (CBL) possesses a space-variant intensity profile due to the spatially polarized atomic medium. Accordingly, the polarization-resolved spectrum can be directly mapped from a single CBL profile and the polarization information of the input 776 nm beam can be accurately extracted. In particular, such nondegenerate FWM based on VB provides a proof of principle for rapid and visual polarization-related detection by converting to a frequency domain where efficient detectors are readily available.