The Efficient Intermodal Four-Wave Mixing Process in a Few-Mode Fibers

The four-wave mixing (FWM) process in a few-mode optical fibers enables parametric light conversion through a third-order nonlinear process [1], [2]. The generated photon pairs correspond to the Stokes and anti-Stokes frequencies and are determined by the phase-matching condition for the particular nonlinear process. Therefore the spectral separation of generated optical fields can be managed by the fiber's dispersion properties and by the utilization of the inter-modal (IM) FWM approach, which is based on the propagation of the pump, Stokes, and anti-Stokes beams in the form of fundamental as well as higher-order modes of few-mode fibers. The IM-FWM has become a popular technique for converting the energy of the pump lasers to visible and infrared spectral regions in light parametric conversion and amplification, as well as in the field of quantum communication science [3].