Speaker
Dr
Omid Noroozian
(NASA Goddard Space Flight Center / UMD)
Description
We are developing a highly integrated photonic spectrometer-on-chip called Microspec for application on space or balloon telescopes for submillimeter/THz astrophysics. All components including the detectors and optical dispersion elements are integrated into a single photonic chip, and utilize a highly confined microstrip architecture for immunity to stray radiation. We use low-loss superconducting niobium transmission lines with a 0.45 μm single-crystal silicon dielectric to produce a synthetic grating with spectral resolution and efficiency ultimately only limited by the intrinsic loss of crystalline Si at cryogenic temperatures. The photon detectors are half-wave resonator microstrip-line KIDs with aluminum top and Nb ground plane on 0.45 µm Si. We have built a laboratory demonstration version of Microspec in the 400—600 GHz band with 48 optical channels that operates with resolution R=64.
We report on the optical measurements of the spectrometer channels, and on dark characterization of the KIDs. We successfully demonstrate end-to-end optical performance that matches the expected resolution of 64, achieve channel yield of 47 out of 48, and obtain uniform channel response. In addition we demonstrate high contrast in overlapping adjacent channels with zero out-of-band response in the 100-800 GHz range. The KIDs exhibit significantly reduced sensitivity performance due to smaller than expected internal quality factors. We present cryogenic microwave loss data that supports the existence of a contaminating hydrocarbon layer at the Si/Nb interface that is supported by transmission electron microscope images.
Primary author
Dr
Omid Noroozian
(NASA Goddard Space Flight Center / UMD)
Co-authors
Dr
Ari D. Brown
(NASA GSFC)
Dr
Edward J. Wollack
(NASA GSFC)
Dr
Emily M. Barrentine
(NASA GSFC)
Dr
Giuseppe Cataldo
(NASA GSFC)
Dr
Harvey (Samuel) Moseley
(NASA GSFC)
Dr
Kongpop U-Yen
(NASA GSFC)
Dr
Negar Ehsan
(NASA GSFC)
Dr
Thomas R. Stevenson
(NASA GSFC)
