Lumped element kinetic inductance detectors maturity for space-borne instruments in the range between 80 and 180 GHz

TL;DR

This paper reviews the current performance of lumped element kinetic inductance detectors (LEKIDs) for space applications in the 80-180 GHz range, focusing on sensitivity and cosmic ray interactions under space-like conditions.

Contribution

It provides a comprehensive assessment of LEKID performance at millimeter wavelengths, including laboratory characterization and modeling for space environment conditions.

Findings

LEKID arrays show promising sensitivity for space-borne instruments.

Cosmic ray interactions cause detectable glitches in LEKID signals.

An analytical model predicts LEKID behavior at the L2 point.

Abstract

This work intends to give the state-of-the-art of our knowledge of the performance of LEKIDs at millimetre wavelengths (from 80 to 180~GHz). We evaluate their optical sensitivity under typical background conditions and their interaction with ionising particles. Two LEKID arrays, originally designed for ground-based applications and composed of a few hundred pixels each, operate at a central frequency of 100, and 150~GHz ($\Delta \nu / \nu$ about 0.3). Their sensitivities have been characterised in the laboratory using a dedicated closed-circle 100~mK dilution cryostat and a sky simulator, allowing for the reproduction of realistic, space-like observation conditions. The impact of cosmic rays has been evaluated by exposing the LEKID arrays to alpha particles ($^{241}$Am) and X sources ($^{109}$Cd) with a readout sampling frequency similar to the ones used for Planck HFI (about 200~Hz), and also with a high resolution sampling level (up to 2~MHz) in order to better characterise and interpret the observed glitches. In parallel, we have developed an analytical model to rescale the results to what would be observed by such a LEKID array at the second Lagrangian point.