Open AccessMode-converters for rectangular-core fiber amplifiers to achieve diffraction-limited power scaling
Author(s) -
Arun Sridharan,
Paul H. Pax,
John E. Heebner,
Derrek R. Drachenberg,
James P. Armstrong,
Jay W. Dawson
Publication year - 2012
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.20.028792
Subject(s) - optics , diffraction , ribbon , equilibrium mode distribution , materials science , mode field diameter , amplifier , energy conversion efficiency , mode volume , fiber , mode (computer interface) , core (optical fiber) , single mode optical fiber , optical fiber , radiation mode , optoelectronics , polarization maintaining optical fiber , computer science , physics , fiber optic sensor , cmos , composite material , operating system
A rectangular-core (ribbon) fiber that guides and amplifies a single higher-order-mode (HOM) can potentially scale to much higher average powers than what is possible in traditional circular-core large-mode-area fibers. Such an amplifier would require mode-conversion at the input to enable interfacing with seed sources that typically output TEM(00) mode radiation and at the output to generate diffraction-limited radiation for end-user applications. We present the first simulation and experimental results of a mode conversion technique that uses two diffractive-optic-elements in conjugate Fourier planes to convert a diffraction limited TEM(00) mode to the HOM of a ribbon fiber. Mode-conversion-efficiency is approximately 84% and can theoretically approach 100%. We also demonstrate a mode-converter system that converts a single HOM of a ribbon fiber back to a diffraction-limited TEM(00) mode. Conversion efficiency is a record 80.5%.