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arXiv · 2103.14047

Simulations of mode-selective photonic lanterns for efficient coupling of starlight into the single-mode regime

Momen Diab·Aashana Tripathi·John Davenport·Aline N. Dinkelaker·Kalaga Madhav·Martin M. Roth
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Abstract

In ground-based astronomy, starlight distorted by the atmosphere couples poorly into single-mode waveguides but a correction by adaptive optics, even if only partial, can boost coupling into the few-mode regime allowing the use of photonic lanterns to convert into multiple single-mode beams. Corrected wavefronts result in focal patterns that couple mostly with the circularly symmetric waveguide modes. A mode-selective photonic lantern is hence proposed to convert the multimode light into a subset of the single-mode waveguides of the standard photonic lantern, thereby reducing the required number of outputs. We ran simulations to show that only two out of the six waveguides of a 1x6 photonic lantern carry >95% of the coupled light to the outputs at $D/r_0 < 10$ if the wavefront is partially corrected and the photonic lantern is made mode-selective.

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Momen Diab, Aashana Tripathi, John Davenport, Aline N. Dinkelaker, Kalaga Madhav, Martin M. Roth. 2021-03-25. Simulations of mode-selective photonic lanterns for efficient coupling of starlight into the single-mode regime. https://doi.org/10.1364/ao.421799

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