Linearized SQUID Array (LISA) for High Bandwidth Frequency-Domain Readout Multiplexing

TL;DR

This paper introduces a linearized SQUID array (LISA) with cryogenic feedback, achieving high bandwidth and linearity suitable for multiplexed readout of sensors, improving over traditional SQUID flux-locked loops.

Contribution

The paper presents a novel 300-element series array SQUID with cryogenic feedback, enabling significantly increased bandwidth and linearity for sensor readout applications.

Findings

LISA achieves larger flux-locked loop bandwidth.

LISA demonstrates sufficient linearity and noise performance.

LISA is suitable for multiplexed TES bolometer readout.

Abstract

We have designed and demonstrated a Superconducting Quantum Interference Device (SQUID) array linearized with cryogenic feedback. To achieve the necessary loop gain a 300 element series array SQUID is constructed from three monolithic 100-element series arrays. A feedback resistor completes the loop from the SQUID output to the input coil. The short feedback path of this Linearized SQUID Array (LISA) allows for a substantially larger flux-locked loop bandwidth as compared to a SQUID flux-locked loop that includes a room temperature amplifier. The bandwidth, linearity, noise performance, and dynamic range of the LISA are sufficient for its use in our target application: the multiplexed readout of transition-edge sensor bolometers.