Thermal and Electrical Properties of Prototype Readout Components for CMB-S4

TL;DR

This paper characterizes the thermal and electrical performance of prototype readout components for CMB-S4, aiming to optimize large-scale detector readout systems for cosmic microwave background observations.

Contribution

It provides new measurements and analysis of wiring and SQUID array components to improve readout performance in large detector arrays.

Findings

Prototype wiring and SQUID arrays meet thermal and electrical performance targets.

Optimized readout components reduce thermal load and improve bandwidth.

Results inform design choices for large-scale CMB-S4 detector readouts.

Abstract

CMB-S4 is the fourth-generation ground-based cosmic microwave background project, designed to probe the early universe and cosmic inflation. CMB-S4 would achieve its science goals in part by dramatically increasing the number of transition edge sensor (TES) bolometer detectors on the sky. The detector readout system for CMB-S4 is time-division multiplexing (TDM) with a two-stage Superconducting Quantum Interference Device (SQUID) system. To accommodate the large increase in detectors, the size of our camera increases, placing physical constraints on the readout, its wiring, and its power dissipation. Therefore, to optimize readout performance, we need to balance competing design considerations such as thermal load and bandwidth. We present results characterizing the thermal and electrical performance of prototype components, including wiring and SQUID arrays for CMB-S4, and discuss the impact on overall system performance.