Patent 10454016 was granted and assigned to Raytheon BBN Technologies on October, 2019 by the United States Patent and Trademark Office.
A photon detector including a graphene-insulating-superconducting junction configured as a temperature sensor. Photons are absorbed by the graphene sheet of the graphene-insulating-superconducting junction, each absorbed photon causing a temporary increase in the temperature of the graphene sheet, and a corresponding change in the differential impedance of the graphene-insulating-superconducting junction. The graphene-insulating-superconducting junction is part of a resonant circuit connected as a shunt load between a radio frequency input transmission line and a radio frequency output transmission line. The transmission S-parameter from input to output is affected by the impedance of the resonant circuit which in turn is affected by the differential impedance of the graphene-insulating-superconducting junction, and therefore by the temperature of the graphene sheet. The absorption of photons is detected by detecting changes in the transmission S-parameter indicating temperature changes caused by the absorption of a photon.