Focal-ratio-degradation (FRD) mitigation in a multimode fiber link using mode-selective photonic lanterns [CL]

http://arxiv.org/abs/2004.04035


We present a new way to mitigate focal-ratio degradation (FRD) when using optical fibers to transport multimode light. Our approach exploits a custom multicore fiber (MCF) with six dissimilar cores that are single mode at ~1550 nm wavelength and minimally coupled over 7 m. We fabricated adiabatic mode-selective photonic lanterns (PLs) at each end of the MCF to create a fiber link with multimode ports, the PLs coupling each spatial mode of the multimode ports to a specific core of the MCF and vice versa. The PL-MCF-PL link exhibits superior FRD behavior compared to a conventional multimode fiber that also supports 6 modes, because it inhibits the transfer of light from lower-order modes to higher-order modes. These results open up a potentially powerful new approach to mitigate FRD in multimode fiber links, with particular applications in astronomical instruments.

Read this paper on arXiv…

A. Benoît, S. Yerolatsitis, K. Harrington, et. al.
Thu, 9 Apr 20
41/54

Comments: 9 pages, 12 figures