The Photonic Lantern Nuller: from concept to laboratory and on-sky demonstrations

Yinzi Xin; Nemanja Jovanovic; Dimitri Mawet; Daniel Echeverri; Yoo Jung Kim; Jonathan Lin; Julien Lozi; Sebastien Vievard; Olivier Guyon; Grace Piroscia; Vincent Deo; Sergio Leon-Saval; Rodrigo Amezcua-Correa; Stephanos Yerolatsitis; Sebastiaan Y. Haffert; Michael P. Fitzgerald; Pradip Gatkine; Suvinay Goyal; Barnaby Norris; Garreth Ruane; Steph Sallum

arXiv · 2608.24308

The Photonic Lantern Nuller: from concept to laboratory and on-sky demonstrations

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Abstract

This thesis work presents the conceptual design and experimental characterization of the Photonic Lantern Nuller instrument, which uses a multimode-to-single-mode demultiplexing waveguide to cancel out starlight while maintaining planet light, allowing for the direct characterization of planets at a telescope's diffraction limit. The PLN was experimentally characterized in the lab, where it was further enhanced using common-path wavefront sensing and control techniques, and then demonstrated on sky at the Subaru Telescope. Highlights include measured in-lab null-depths of $\sim 10^{-4}$ in three out of four ports simultaneously and on-sky null-depths of approximately $\sim 10^{-1}$ (limited by jitter and atmospheric residuals). We provide an overview of these results and discuss avenues for future work.

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Yinzi Xin, Nemanja Jovanovic, Dimitri Mawet, Daniel Echeverri, Yoo Jung Kim, Jonathan Lin, Julien Lozi, Sebastien Vievard, Olivier Guyon, Grace Piroscia, Vincent Deo, Sergio Leon-Saval, Rodrigo Amezcua-Correa, Stephanos Yerolatsitis, Sebastiaan Y. Haffert, Michael P. Fitzgerald, Pradip Gatkine, Suvinay Goyal, Barnaby Norris, Garreth Ruane, Steph Sallum. 2026-08-25. The Photonic Lantern Nuller: from concept to laboratory and on-sky demonstrations. https://arxiv.org/abs/2608.24308

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