Status of SuperSpec: A Broadband, On-Chip Millimeter-Wave Spectrometer

S. Hailey-Dunsheath; E. Shirokoff; P. S. Barry; C. M. Bradford; G. Chattopadhyay; P. Day; S. Doyle; M. Hollister; A. Kovacs; H. G. LeDuc; P. Mauskopf; C. M. McKenney; R. Monroe; R. O'Brient; S. Padin; T. Reck; L. Swenson; C. E. Tucker; J. Zmuidzinas

doi:10.1117/12.2057229

arXiv · 1501.02295

Status of SuperSpec: A Broadband, On-Chip Millimeter-Wave Spectrometer

S. Hailey-Dunsheath·E. Shirokoff·P. S. Barry·C. M. Bradford·G. Chattopadhyay·P. Day·S. Doyle·M. Hollister·A. Kovacs·H. G. LeDuc·P. Mauskopf·C. M. McKenney·R. Monroe·R. O'Brient·S. Padin·T. Reck·L. Swenson·C. E. Tucker·J. Zmuidzinas

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Abstract

SuperSpec is a novel on-chip spectrometer we are developing for multi-object, moderate resolution (R = 100 - 500), large bandwidth (~1.65:1) submillimeter and millimeter survey spectroscopy of high-redshift galaxies. The spectrometer employs a filter bank architecture, and consists of a series of half-wave resonators formed by lithographically-patterned superconducting transmission lines. The signal power admitted by each resonator is detected by a lumped element titanium nitride (TiN) kinetic inductance detector (KID) operating at 100-200 MHz. We have tested a new prototype device that is more sensitive than previous devices, and easier to fabricate. We present a characterization of a representative R=282 channel at f = 236 GHz, including measurements of the spectrometer detection efficiency, the detector responsivity over a large range of optical loading, and the full system optical efficiency. We outline future improvements to the current system that we expect will enable construction of a photon-noise-limited R=100 filter bank, appropriate for a line intensity mapping experiment targeting the [CII] 158 micron transition during the Epoch of Reionization

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S. Hailey-Dunsheath, E. Shirokoff, P. S. Barry, C. M. Bradford, G. Chattopadhyay, P. Day, S. Doyle, M. Hollister, A. Kovacs, H. G. LeDuc, P. Mauskopf, C. M. McKenney, R. Monroe, R. O'Brient, S. Padin, T. Reck, L. Swenson, C. E. Tucker, J. Zmuidzinas. 2015-01-10. Status of SuperSpec: A Broadband, On-Chip Millimeter-Wave Spectrometer. https://doi.org/10.1117/12.2057229

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