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arXiv · 2607.03280

Seidr update: photonic 'black magic' for high-contrast interferometry using kernel-nulling and photonic lanterns

Nathan K Long·Daniel S Dahl·Christopher H Betters·Julia J Bryant·Nick Cvetojevic·Michael J Ireland·Stefan Kraus·Sergio Leon-Saval·Frantz Martinache·Marc-Antoine Martinod·Barnaby Norris·Jyotirmay Paul·Akira Rodziewicz-Ryan·Adam K Taras·Jin Wei·Peter G Tuthill
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Abstract

Seidr is a new interferometric beam combiner within the Asgard Suite, utilizing infrastructure common to the BIFROST instrument at the Very Large Telescope Interferometer. Seidr combines hybrid mode-selective photonic lantern injection modules with a kernel-nulling photonic chip backend to enable deep H-band nulling for high-contrast studies of exoplanets, exomoons, and circumstellar dust. This instrument update summarizes Seidr's current design maturity and recent simulations of the point source - to - lantern outputs. We also outline progress on our neural network-based wavefront estimation scheme, which uses the photonic lantern outputs to sense phase fluctuations, designed to feed back to Baldr's deformable mirror, and improve nuller light injection.

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Nathan K Long, Daniel S Dahl, Christopher H Betters, Julia J Bryant, Nick Cvetojevic, Michael J Ireland, Stefan Kraus, Sergio Leon-Saval, Frantz Martinache, Marc-Antoine Martinod, Barnaby Norris, Jyotirmay Paul, Akira Rodziewicz-Ryan, Adam K Taras, Jin Wei, Peter G Tuthill. 2026-07-03. Seidr update: photonic 'black magic' for high-contrast interferometry using kernel-nulling and photonic lanterns. https://arxiv.org/abs/2607.03280

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