2020/04/08 by Aurélien Benoît, Benoît, Aurélien, Stephanos Yerolatsitis +7
Engineering · #Advanced Optical Network Technologies #FOS: Physical sciences #Instrumentation and Methods for Astrophysics (astro-ph.IM) #Optical Network Technologies #Optics (physics.optics) #Semiconductor Lasers and Optical Devices
paper · pdf · doi:10.48550/arxiv.2004.04035
openalex publication_date 2020/04/08 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
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.