Design and performance of the antenna coupled lumped-element kinetic inductance detector

TL;DR

This paper introduces a novel antenna-coupled lumped-element kinetic inductance detector design, demonstrating its potential for large-scale, polarization-sensitive CMB observations with promising preliminary performance results.

Contribution

It presents a new KID variant with antenna coupling and optimized design, advancing the development of scalable, polarization-sensitive detector arrays for CMB experiments.

Findings

Prototype arrays show expected resonant behavior.

Preliminary results align with model predictions.

Design enhances multiplexing capabilities.

Abstract

Focal plane arrays consisting of low-noise, polarisation-sensitive detectors have made possible the pioneering advances in the study of the cosmic microwave background (CMB). To make further progress, the next generation of CMB experiments (e.g. CMB-S4) will require a substantial increase in the number of detectors compared to the current stage 3 instruments. Arrays of kinetic inductance detectors (KIDs) provide a possible path to realising such large format arrays owing to their intrinsic multiplexing advantage and relative cryogenic simplicity. In this proceedings, we report on the design of a novel variant of the traditional KID design; the antenna-coupled lumped-element KID. A polarisation sensitive twin-slot antenna placed behind an optimised hemispherical lens couples power onto a thin-film superconducting microstrip line. The power is then guided into the inductive section of an aluminium KID where it is absorbed and modifies both the resonant frequency and quality factor of the KID. We present the various aspects of the design and preliminary results from the first set of seven-element prototype arrays and compare to the expected modelled performance.