Using SQUIDs to Detect Charge in Cryogenic Germanium Detectors.

This paper describes an impedance matching network which allows charge impulses to be measured by a SQUID amplifier with an RMS charge noise of less than 100 e, assuming the SQUID amplifier has a current noise of 2 $\mathrm{pA}/\sqrt{\mathrm{Hz}}$, and the current pulse has a duration of about 1 μs or shorter. The component values are provided for an example system which has an RMS charge noise of 91 e, assuming all dissipative circuit elements are cooled to a temperature of 100 mK. [ABSTRACT FROM AUTHOR]