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arXiv · 2006.10323

Multiple spatial and wavelength conversion operations based on a frequency-degenerated intermodal four-wave-mixing process in a graded-index 6-LP few mode fiber

H. Zhang·M. Bigot-Astruc·P. Sillard·G. Millot·B. Kibler·Julien Fatome
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Abstract

We report on the experimental observation of a simultaneous threefold wavelength and spatial conversion process at telecommunication wavelengths taking place in a 6-LP-mode graded-index few-mode fiber. The physical mechanism is based on parallel and phase-matched frequency-degenerated intermodal four-wave mixing (FD-IFWM) phenomena occurring between the fundamental mode and higher-order spatial modes. More precisely, a single high-power frequency-degenerated pump wave is simultaneously injected in the four spatial modes LP01, LP11, LP02 and LP31 of a 1.8-km long graded-index few-mode fiber together with three independent signals in the fundamental mode. By means of three parallel phase-matched FD-IFWM interactions, these initial signals are then simultaneously spatially and frequency converted from the fundamental mode to specific high-order modes. The influence of the differential modal group delay is also investigated and shows that the walk-off between the spatially multiplexed signals significantly limits the bandwidth of the conversion process for telecom applications.

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H. Zhang, M. Bigot-Astruc, P. Sillard, G. Millot, B. Kibler, Julien Fatome. 2020-06-18. Multiple spatial and wavelength conversion operations based on a frequency-degenerated intermodal four-wave-mixing process in a graded-index 6-LP few mode fiber. https://doi.org/10.1364/ao.393299

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