Optimization of an Optical Testbed for Characterization of EXCLAIM u-Spec Integrated Spectrometers

Maryam Rahmani; Emily M. Barrentine; Eric R. Switzer; Alyssa Barlis; Ari D. Brown; Giuseppe Cataldo; Jake A. Connors; Negar Ehsan; Thomas M. Essinger-Hileman; Henry Grant; James Hays-Wehle; Wen-Ting Hsieh; Vilem Mikula; S. Harvey Moseley; Omid Noroozian; Manuel A. Quijada; Jessica Patel; Thomas R. Stevenson; Carole Tucker; Kongpop U-Yen; Carolyn G. Volpert; Edward J. Wollack

arXiv · 2312.07656

Optimization of an Optical Testbed for Characterization of EXCLAIM u-Spec Integrated Spectrometers

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Abstract

We describe a testbed to characterize the optical response of compact superconducting on-chip spectrometers in development for the Experiment for Cryogenic Large-Aperture Intensity Mapping (EXCLAIM) mission. EXCLAIM is a balloonborne far-infrared experiment to probe the CO and CII emission lines in galaxies from redshift 3.5 to the present. The spectrometer, called u-Spec, comprises a diffraction grating on a silicon chip coupled to kinetic inductance detectors (KIDs) read out via a single microwave feedline. We use a prototype spectrometer for EXCLAIM to demonstrate our ability to characterize the spectrometers spectral response using a photomixer source. We utilize an on-chip reference detector to normalize relative to spectral structure from the off-chip optics and a silicon etalon to calibrate the absolute frequency.

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Maryam Rahmani, Emily M. Barrentine, Eric R. Switzer, Alyssa Barlis, Ari D. Brown, Giuseppe Cataldo, Jake A. Connors, Negar Ehsan, Thomas M. Essinger-Hileman, Henry Grant, James Hays-Wehle, Wen-Ting Hsieh, Vilem Mikula, S. Harvey Moseley, Omid Noroozian, Manuel A. Quijada, Jessica Patel, Thomas R. Stevenson, Carole Tucker, Kongpop U-Yen, Carolyn G. Volpert, Edward J. Wollack. 2023-12-12. Optimization of an Optical Testbed for Characterization of EXCLAIM u-Spec Integrated Spectrometers. https://arxiv.org/abs/2312.07656

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