Presentation Information
[EDP1-06]Development of High-sensitivity Superconducting Kinetic Inductance Detectors for Far-infrared and Mid-infrared Astronomy
*Runfeng Su1, Rui Tan1, Junhua Chen1, Yuwei Zhu1, Tianyuan Chi1, Siming Zang1, Jingbo Wu1,2, Xuecou Tu1,2, Jian Chen1,2, Peiheng Wu1,2 (1. Research Institute of Superconductor Electronics (RISE), School of Electronic Science and Engineering, Nanjing University (China), 2. Purple Mountain Laboratory (China))
Keywords:
Kinetic Inductance Detector,FIR,MIR,Noise Equivalent Power
We reported high-sensitivity superconducting KIDs designed for the far-infrared (FIR) and mid-infrared (MIR) bands. The KIDs are lumped-element resonators, each comprising a tantalum interdigitated-capacitor and an aluminum inductor. The inductor also serves as the absorber. The capacitor and coplanar waveguide feedlines are fabricated from a 150-nm-thick tantalum film, while the inductor is composed of a 40-nm-thick aluminum film. At a bath temperature of 100 mK in a dark environment, the KIDs exhibit an intrinsic quality factor on the order of 105. The FIR KID operates at 4.3 THz (λ≈70 μm), while the MIR KID operates at 15 THz (λ≈20 μm). For the FIR KID, the absorber consists of periodic hairpin units with individual linewidths of 100 nm and a small volume of ~4.3 μm3. The simulated polarization-averaged absorption efficiency is ~68% at 4.3 THz. For the MIR KID, the absorber consists of periodic dipole units with individual linewidths of 400 nm and a volume of ~44 μm3. The simulated polarization-averaged absorption efficiency is ~76% at 15 THz. At a bath temperature of 100 mK, the optical noise equivalent power (NEP) was characterized using cryogenic blackbody radiation. The optical NEP is ~1.9x10-19 W•Hz-0.5 for the FIR KID and ~2.9x10-18 W•Hz-0.5 for the MIR KID. These high-sensitivity KIDs have potential for ground-based, balloon-borne, and space platforms in astronomical observations across both the FIR and MIR bands.