Millimeter-Wavelength Lens-Absorber-Coupled Ti/Al Kinetic Inductance Detectors
Abstract
This work presents Ti/Al bi-layer Microwave Kinetic Inductance Detectors (MKIDs) based on lens-coupled spiral absorbers as the quasi-optical coupling mechanism for millimeterwavelength radiation detection. From simulations, the lenscoupled absorbers provide a 70% lens aperture efficiency in both polarizations over an octave band with a spiral array absorber and over 10% relative bandwidth with a single spiral. We have fabricated and measured two devices with bare Ti/Al MKIDs: a$ 3 \times 3$cm chip with 9 pixels to characterize the optical response at 85GHz of the two variations of the absorber; and a large format demonstrator with 253 spiral-array pixels showing potential towards a large format millimeter-wavelength camera. We estimate a sensitivity of$ 1 \, \rm{mK} / \sqrt{\rm{Hz}}$and a$ 95\%$detector yield.
Fields of Study & Subjects
Superconducting and THz Device Technology
Terahertz technology and applications
Metamaterials and Metasurfaces Applications
Publication details
- Journal / source
- IEEE Transactions on Applied Superconductivity
- Publisher
- Institute of Electrical and Electronics Engineers (IEEE)
- Volume
- 36
- Issue
- 6
- Pages
- 1–8
- Publication date
- 17 February 2026
- Language
- EN