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Updated: Aug 11, 2026

Low-cost Custom Fabrication and Mode-locked Operation of an All-normal-dispersion Femtosecond Fiber Laser for Multiphoton Microscopy
Published on: November 22, 2019
Ultralong Raman fiber lasers as virtually lossless optical media
Juan Diego Ania-Castañón1, Tim J Ellingham, R Ibbotson
1Photonics Research Group, School of Engineering and Applied Science, Aston University, Birmingham, B47ET, United Kingdom.
Abstract:
By transforming the optical fiber span into an ultralong cavity laser, we experimentally demonstrate quasilossless transmission over long (up to 75 km) distances and virtually zero signal power variation over shorter (up to 20 km) spans, opening the way for the practical implementation of integrable nonlinear systems in optical fiber. As a by-product of our technique, the longest ever laser (to the best of our knowledge) has been implemented, with a cavity length of 75 km. A simple theory of the lossless fiber span, in excellent agreement with the observed results, is presented.
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