Laser Physics Letters

Dressed optical vortex in a hot atomic medium

Lanxiao Huang, Zhiguo Wang, Yanyong Sun, Xinghua Li, Yanpeng Zhang

Published Aug 8, 2019• 0 citations

Abstract

Abstract We experimentally observe the vortex six-wave mixing (SWM) signal carrying orbital angular momentum in a photonic band gap structure. First, we scan the probe detuning and the detuning of the dressing field to find an explanation for the intensity variation of four-wave mixing (FWM) intensity and the shift of forks in interference patterns. Then we change the power of the coupling field and obtain SWM images as well as its interference patterns to investigate the propagation characteristics, including spatial shift and splitting. We observe a change of fork quantity when decreasing the incident angle of the probe field. We suppose that the reflected signal is a combination of a linear probe and a nonlinear vortex FWM signal. By changing the incident angle of the field, the overlap condition between fields have changed correspondingly and the cross-Kerr effect of the coupling field on the linear vortex probe and third-order FWM become different, causing a separation in the center of the two components, which brings the inducement of additional forks.

DOI: 10.1088/1612-202x/ab33f9

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