Speaker
Description
In several proposed dark matter direct detection experiments, microwave photons in the THz/meV range are incident on a focal plane of detectors sensitive to single energy deposition events. Although various types of sensors have been proposed, none have yet demonstrated the ability to resolve single THz photon or meV phonon events across a wide bandwidth. The superconducting quasiparticle amplifying transmon (SQUAT) is a new detector architecture based on a weakly charge-sensitive transmon qubit directly coupled to a transmission line. In the SQUAT, a meV-scale (THz) event breaks Cooper pairs in the qubit’s capacitor islands, generating quasiparticles which then tunnel across the Josephson junction and produce a measurable signal in the qubit’s parity switching rate. Importantly, the SQUAT is not coupled to a readout resonator, allowing for a much higher pixel density on chip and continuous high-bandwidth measurement. Here, we discuss the design and first characterization results of SQUATs and their application to future axion dark matter experiments, particularly BREAD.
| Main Contribution topic | Instrumentation for Dark Matter searches |
|---|---|
| Secondary contribution topic | Axion / Sterile |