@inproceedings{1e284c92d6c749c7b00ee7b321cb79f2,
title = "A focal-ratio-degradation resistant multimode fiber link using mode-selective photonic lantern",
abstract = "We report a new route to mitigate focal-ratio degradation (FRD) in multimode optical fiber links. Our approach uses a custom multicore fiber (MCF) with dissimilar cores, which is then tapered at both ends to form multimode cores and create mode-selective photonic lantern (PL) transitions. The cores of the MCF are single-moded at 1550 nm and sufficiently spaced such that there is no observable core-To-core cross talk after a 7 m fiber length. The mode-selective PLs at each end of the MCF, in combinations with the low core-To-core cross talk of the MCF at 1550 nm, ensure that the relative amount of power in each spatial mode is preserved throughout the fibre link. As such, a PL-MCF-PL link using this approach has the potential to be resistant to FRD by inhibiting the coupling of light from lower-order to higher-order modes. We show that the full PL-MCF-PL link exhibits lower FRD than a custom multimode fiber that guides the same number of modes. A study of how the FRD behavior of the PL-MCF-PL link varies as a function of wavelength indicates some bandwidth limitations due to the wavelength-dependent properties of the PLs and the cross coupling in the MCF. ",
keywords = "Focal ratio degradation, integral fiber-fed spectrograph, photonic lantern",
author = "Aurelien Benoit and Stephanos Yerolatsitis and Kerrianne Harrington and Birks, {Tim A.} and Thomson, {Robert R.}",
note = "Funding Information: This work was funded by the UK STFC through grants ST/N000544/1 and ST/N000625/1, and by the European Union Horizon 2020 grant 730890 (OPTICON). Publisher Copyright: {\textcopyright} 2020 SPIE.; SPIE Astronomical Telescopes + Instrumentation 2020 ; Conference date: 14-12-2020 Through 22-12-2020",
year = "2020",
month = dec,
day = "13",
doi = "10.1117/12.2561438",
language = "English",
isbn = "9781510636897",
series = "Proceedings of SPIE ",
publisher = "SPIE",
editor = "Ramon Navarro and Roland Geyl",
booktitle = "Advances in Optical and Mechanical Technologies for Telescopes and Instrumentation IV",
address = "United States",
}