A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. In some embodiments the waveguide is omitted and infrared light propagating in free space illuminates the graphene sheet directly. A photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet. The graphene sheet is coupled to the weak link of a Josephson junction, and a constant bias current is driven through the Josephson junction, so that an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.

A detector for detecting single photons of infrared radiation or longer wavelength electromagnetic radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. In other embodiments a transmission line or antenna is coupled to the graphene sheet and guides longer-wavelength photons to the graphene sheet. A photon absorbed by the graphene sheet heats the graphene sheet. Part of the graphene sheet is part of the Josephson junction as the weak link, and a constant bias current is driven through the Josephson junction; an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.

A detector for detecting single photons of infrared radiation. In one embodiment a waveguide configured to transmit infrared radiation is arranged to be adjacent a graphene sheet and configured so that evanescent waves from the waveguide overlap the graphene sheet. An infrared photon absorbed by the graphene sheet from the evanescent waves heats the graphene sheet. The graphene sheet is coupled to the weak link of a Josephson junction, and a constant bias current is driven through the Josephson junction, so that an increase in the temperature of the graphene sheet results in a decrease in the critical current of the Josephson junction and a voltage pulse in the voltage across the Josephson junction. The voltage pulse is detected by the pulse detector.

A semiconductor radiation detector comprises a detector chip having a front side and a back side, and a support plate on the back side of the detector chip, having electric connections with said detector chip. A base plate has a thermoelectric cooler attached to it and contact pins protruding from the base plate towards said detector chip. A bonding plate is on an opposite side of said thermoelectric cooler than said base plate, and first wire bonded connections go between said contact pins and said bonding plate. A joint plate is between said bonding plate and said support plate, and electric connections between said support plate and said bonding plate go through said joint plate.

Some aspects are directed to an all-on-chip, optoelectronic device for sampling arbitrary, low-energy, near-infrared waveforms under ambient conditions. This solid-state integrated detector uses optical-field-driven electron emission from resonant nanoantennas to achieve petahertz-level switching speeds by generating on-chip attosecond electron burst. Also disclosed is a cross-correlation technique based on perturbation of local electron field emission rates that allows for the full characterization of arbitrary electric fields down to 1 femtojoule, and/or on the order of 500 kV/m, using plasmonic nanoantennas.

Methods, systems, and apparatus, for a stray-light testing station. In one aspect, the stray-light testing station includes an illumination assembly including a spatially extended light source and one or more optical elements arranged to direct a beam of light from the spatially extended light source along an optical path to an optical receiver assembly including a lens receptacle configured to receive a lens module and position the lens module in the optical path downstream from the parabolic mirror so that the lens module focuses the beam of light from the spatially extended light source to an image plane, and a moveable frame supporting the optical receiver assembly including one or more adjustable alignment stages to position the optical receiver assembly relative to the illumination assembly such that the optical path of the illumination assembly is within a field of view of the optical receiver assembly.

A receiver according to an embodiment is a terahertz band receiver including an antenna configured to receive a terahertz band signal reflected or transmitted from a measurement target, a detector configured to receive a differential signal including a first input signal V.sub.THz and a second input signal V.sub.THz with phase difference of 180 to each other from the antenna to detect a voltage, and operate in a concurrent mode, and a buffer amplifier configured to amplify and output a signal detected by the detector.

Disclosed is a sensor fabric for detecting an attack on transistors. The fabric includes a plurality of sensor clusters. Each sensor cluster comprises a plurality of photodetectors and transistors, each photodetector being disposed next to a respective said transistor, a standard cell and an aggregator. The standard cell comprising a thresholding comparator for comparing a first input from a first group of the photodetectors of the respective cluster and a second input from a second group of the photodetectors of the respective cluster, the first input and second input being proportional to incident light sensed by the respective photodetectors, and flipping an output of the standard cell if a difference between the first input and second input exceeds a predetermined threshold. The aggregator aggregates the outputs from the clusters to produce an aggregated output, and triggering an alarm on detection of an attack based on the aggregated output.

An example photon detecting system includes a detector component optically coupled to a waveguide and configured to detect one or more photons from the waveguide. The example photon detecting system further includes an optical switch configured to selectively couple the waveguide to an optical source, wherein the optical switch is configured to de-couple the waveguide from the optical input in accordance with the detector component being in an inactive state. The example photon detecting system also includes readout circuitry coupled to the detector component.

Disclosed is a single photon detector comprising a semiconductor substrate and a 2D material layer provided adjacent to the semiconductor substrate, the semiconductor substrate includes a first well having a first conductivity type, a heavily doped region having a second conductivity type different from the first conductivity type, and a depletion region provided between the first well and the heavily doped region.