Presentation #244.08 in the session New Approaches — iPoster Session.
The development of large arrays of highly sensitive detectors is the key technological hurdle for future far-infrared spectrometers on space-based telescopes. In this presentation we will discuss recent advances in the development of large arrays of sensitive Kinetic Inductance Detectors (KIDs) for the Terahertz Intensity Mapper (TIM) and future far-infrared Probe-class missions as recommended by the Astro2020 decadal survey. TIM is a NASA far-infrared Antarctic balloon mission and an important stepping stone for future space missions. It aims to unravel the 3D structure of the dust-obscured star-forming Universe by performing a spectroscopic survey of the 1.57 THz [CII] fine structure line at 0.5<z<1.7. To achieve this goal, TIM will fly two grating spectrometers that together cover the 240 to 420 μm wavelength range at an R~250. Each spectrometer will require large format arrays (4x~900 detectors) of dual-polarization sensitive detectors, which are photon noise limited at 100 fW of loading. We will demonstrate the performance of a kilopixel array of horn-coupled KIDs that incorporates a novel “chain-link” absorber design. Operating at 215 mK, we demonstrate that this detector achieves a photon noise limited performance at 80 fW of optical loading with a white noise spectrum down to 1 Hz. Informed by dark measurements, we expect these KIDs to achieve a detector limited NEP of ~1e-18 W/Hz0.5 (30 times more sensitive than the bolometers on Herschel SPIRE). This easily satisfies the requirements set by TIM. Looking forward, the envisioned far-infrared Probe-class space missions with fully cryogenic optics, will require arrays with detector NEP<1e-19 W/Hz0.5. This can be obtained with smaller-volume devices. We will show our preliminary results of KID that are designed to satisfy this more stringent requirement.