Photonic spatial reformatting of stellar light for diffraction-limited spectroscopy
Robert J. Harris, David G. MacLachlan, Debaditya Choudhury, Tim J. Morris, Eric Gendron, Alastair G. Basden, Graeme Brown, Jeremy R. Allington-Smith, Robert R. Thomson
The spectral resolution of a dispersive spectrograph is dependent on the width of the entrance slit. This means that astronomical spectrographs trade-off throughput with spectral resolving power. Recently, optical guided-wave transitions known as photonic lanterns have been proposed to circumvent this trade-off, by enabling the efficient reformatting of multimode light into a pseudo-slit which is highly multimode in one axis, but diffraction-limited in the other. Here, we demonstrate the successful reformatting of a telescope point spread function into such a slit using a three-dimensional integrated optical waveguide device, which we name the photonic dicer. Using the CANARY adaptive optics demonstrator on the William Herschel Telescope, and light centred at 1530 nm with a 160 nm FWHM, the device shows a transmission of between 10 and 20\% depending upon the type of AO correction applied. Most of the loss is due to the overfilling of the input aperture in poor and moderate seeing. Taking this into account, the photonic device itself has a transmission of 57 $\pm$ 4\%.We show how a fully-optimised device can be used with AO to provide efficient spectroscopy at high spectral resolution.
FIRST-PL: Commissioning the first visible photonic lantern spectrograph for sub-diffraction-limit astronomy on Subaru/SCExAO
University of Hawai‘i（夏威夷大学）；University of Hawaii at Manoa（夏威夷大学马诺阿分校）；Subaru Telescope, National Astronomical Observatory of Japan（昴星团望远镜，日本国立天文台）；Observatoire de Paris, Université PSL（巴黎天文台，巴黎文理研究大学）；Steward Observatory, University of Arizona（斯图尔德天文台，亚利桑那大学）；Astrobiology Center（天体生物学中心）；Univ. Grenoble Alpes, CNRS, IPAG（格勒诺布尔阿尔卑斯大学，法国国家科学研究中心，IPAG）；University of California, Los Angeles（加州大学洛杉矶分校）；Sydney Institute for Astronomy, School of Physics, The University of Sydney（悉尼天体物理研究所，悉尼大学物理学院）；Optical Sharpeners（光学锐化器）；California Institute of Technology（加州理工学院）；Sydney Astrophotonic Instrumentation Laboratory, School of Physics, The University of Sydney（悉尼天体光子仪器实验室，悉尼大学物理学院）；Astralis, School of Physics, University of Sydney（Astralis，悉尼大学物理学院）；University of Texas, San Antonio（得克萨斯大学圣安东尼奥分校）
NAIR-APREXIS: Enabling photonics-based instruments for long-baseline interferometry and integral-field spectroscopy
I. Physikalisches Institut, Universität zu Köln（科隆大学第一物理研究所）；Centre for Advanced Instrumentation, Department of Physics, Durham University（杜伦大学物理系先进仪器中心）；Leibniz-Institut für Astrophysik Potsdam（波茨坦莱布尼茨天体物理研究所）；Institute of Photonics and Quantum Sciences, Heriot-Watt Univ.（赫瑞-瓦特大学光子与量子科学研究所）；The CHARA Array of Georgia State University, Mount Wilson Observatory（佐治亚州立大学CHARA阵列威尔逊山天文台）；Corning Optical Communications GmbH & Co. KG（康宁光学通信有限公司）
