Visible Photonic Lantern integration, characterization and on-sky testing on Subaru/SCExAO

TL;DR

This paper reports the integration and on-sky testing of a visible Photonic Lantern with the Subaru/SCExAO system, demonstrating a twelvefold increase in throughput for high-resolution spectroscopy at small angular scales.

Contribution

It presents the first on-sky demonstration of a visible Photonic Lantern coupled with an adaptive optics system, showing significant performance improvements.

Findings

12x increase in throughput compared to single-mode fiber

Successful integration of PL with SCExAO system

Potential for high throughput photonic instrumentation

Abstract

A Photonic Lantern (PL) is a novel device that efficiently converts a multi-mode fiber into several single-mode fibers. When coupled with an extreme adaptive optics (ExAO) system and a spectrograph, PLs enable high throughput spectroscopy at high angular resolution. The Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) system of the Subaru Telescope recently acquired a PL that converts its multi-mode input into 19 single-mode outputs. The single mode outputs feed a R~4,000 spectrograph optimized for the 600 to 760 nm wavelength range. We present here the integration of the PL on SCExAO, and study the device performance in terms of throughput, field of view, and spectral reconstruction. We also present the first on-sky demonstration of a Visible PL coupled with an ExAO system, showing a significant improvement of x12 in throughput compared to the use of a sole single-mode fiber. This work paves the way towards future high throughput photonics instrumentation at small angular resolution.