Towards a Graphene Josephson Junction Terahertz Single-Photon Detector

Josephson junctions with graphene weak links (GJJs) have emerged as a promising platform for the detection of single photons. Combining the exceptionally small electronic heat capacity of graphene with the strongly temperature-dependent switching of current-biased Josephson junctions, these devices are capable of operating at low photon energies, with low dark count rates, and with detection efficiencies approaching unity when coupled to an appropriate resonant structure. Here we present progress in the design, fabrication, and testing of an antenna-coupled GJJ single photon detector designed for operation at 0.8 THz. Such detectors could find important applications in future space-based far-infrared observatories and the search for dark matter axions.