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arXiv · 2405.01436

High-gain far-detuned nonlinear frequency conversion in optical fibers: intramodal vs. intermodal processes

Karolina Stefańska·Pierre Béjot·Julien Fatome·Guy Millot·Karol Lech Tarnowski·Bertrand Kibler
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Abstract

We present theoretical and experimental evidence of high-gain far-detuned nonlinear frequency conversion, extending towards both the visible and the mid-infrared, in a few-mode graded-index silica fiber pumped at 1.064 $\mu$m, and more specifically achieving gains of hundreds of dB per meter below 0.65 $\mu$m and beyond 3.5 $\mu$m. Our findings highlight the potential of graded-index fibers in terms of strong modal confinement over an ultrabroad spectral range for enabling high-gain wavelength conversion. Such advancements require an accurate interpretation of intramodal and intermodal four-wave mixing processes.

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Karolina Stefańska, Pierre Béjot, Julien Fatome, Guy Millot, Karol Lech Tarnowski, Bertrand Kibler. 2024-05-02. High-gain far-detuned nonlinear frequency conversion in optical fibers: intramodal vs. intermodal processes. https://arxiv.org/abs/2405.01436

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