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arXiv · 2610.26282

Study of non-uniformity-induced structured spectrum in a tapered optical fiber through stimulated four-wave mixing

Minjae Hong·Nicolas Y. Joly
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Abstract

Tapered optical fibers offer tunable dispersion and a small mode area, yielding high nonlinearity, which makes them ideal for nonlinear and quantum optics. Because phase-matched four-wave mixing strongly depends on dispersion, the taper diameter becomes a key parameter. For sub-micrometer tapers, identifying the exact diameter is challenging. Here, we show that when seeding with a broad spectrum, stimulated four-wave mixing yields a comb-like spectrum that is directly linked to the overall taper profile opening possibility for non-destructive evaluation of sub-micron taper. Our model based on joint-spectral amplitude includes the phase accumulated over the fiber length.

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Minjae Hong, Nicolas Y. Joly. 2026-10-19. Study of non-uniformity-induced structured spectrum in a tapered optical fiber through stimulated four-wave mixing. https://arxiv.org/abs/2610.26282

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