An 8 16 pixel array based on CMOS small-area silicon photomultipliers (mini-SiPMs) detectors for PET applications is reported. Each pixel is 570 610 m in size and contains four digital mini-SiPMs, for a total of 720 SPADs, resulting in a full chip fill-factor of 35.7%. For each gamma detection, the pixel provides the total detected energy and a timestamp, obtained through two 7-b counters and two 12-b 64-ps TDCs. An adder tree overlaid on top of the pixel array sums the sensor total counts at up to 100 Msamples/s, which are then used for detecting the asynchronous gamma events on-chip, while also being output in realtime. Characterization of gamma detection performance with an 3 3 5 mm LYSO scintillator at 20 C is reported, showing a 511-keV gamma energy resolution of 10.9% and a coincidence timing resolution of 399 ps.

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Quantum imaging exploits the spatial correlations between photons to image object features with a higher resolution than a corresponding classical light source could achieve. Using a quantum correlated N -photon state, the method of optical centroid measurement (OCM) was shown to exhibit a resolution enhancement by improving the classical Rayleigh limit by a factor of 1/N . In this work, the theory of OCM is formulated within the framework of an imaging formalism and is implemented in an exemplary experiment by means of a conventional entangled photon pair source. The expected resolution enhancement of a factor of two is demonstrated. The here presented experiment allows for single-shot operation without scanning or iteration to reproduce the object in the image plane. Thereby, photon detection is performed with a newly developed integrated timeresolving detector array. Multi-photon interference effects responsible for the observed resolution enhancement are discussed and possible alternative implementation possibilities for higher photon number are proposed.

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We report on room temperature detection of terahertz radiation by means of antenna-coupled field effect transistors (FETs) fabricated using epitaxial graphene grown on silicon carbide. The achieved photoresponsivity (similar to 0.25 V/W) and noise equivalent power (similar to 80 nW/root Hz) result from the combined effect of two independent detection mechanisms: over-damped plasma wave rectification and thermoelectric effects, the latter ascribed to the presence of carrier density junctions along the FET channel. The calculated plasmonic and thermoelectric response reproduces qualitatively well the measured photovoltages; the experimentally observed sign-switch demonstrates the stronger contribution of plasmonic detection compared to the thermoelectric one. These results unveil the potential of plasmonic detectors exploiting epitaxial graphene on silicon carbide for fast large area imaging of macroscopic samples