5results about How to "Reduce dark count" patented technology

The invention provides a single-photon avalanche photodiode, a manufacturing method and an electronic device comprising the single-photon avalanche photodiode, the single-photon avalanche photodiode comprises a P-type substrate layer, an N-type buried layer, a P-type epitaxial layer arranged on the P-type substrate layer, a P-type well arranged in the P-type epitaxial layer, a P-type gate arranged on the N-type buried layer, a P-type gate arranged on the P-type epitaxial layer, and a P-type gate arranged on the N-type buried layer, the upper surface of the P-type well is lower than the upper surface of the P-type epitaxial layer. The lower surface of the P-type well is in contact with the N-type buried layer, the P-type well and the N-type buried layer form a PN junction, the P + region is arranged in the P-type epitaxial layer, the lower surface of the P + region is higher than the upper surface of the N-type buried layer, the P + region surrounds the P-type well and the N + region and is in contact with the N-type buried layer, the lower surface of the N + region is below the upper surface of the N-type buried layer, and the N + region surrounds the P-type well.

The application discloses a kind of micro-wave single-photon detectors and methods.Therein, the detector includes: metal cavity cavity, including first resonant cavity and second resonant cavity, one side of first resonant cavity is equipped with first probe, one side of second resonant cavity is equipped with second probe and third probe, second probe is connected with the control reading signal input port of micro-wave single-photon detector, third probe is connected with the control reading signal output port of micro-wave single-photon detector;Multi-port device, the first port of multi-port device is connected with the micro-wave single-photon input port of micro-wave single-photon detector, the second port of multi-port device is connected with first probe, the third port of multi-port device is connected with first probe and is connected with the micro-wave single-photon output port of micro-wave single-photon detector;Superconducting quantum bits, traverse first resonant cavity and second resonant cavity.The application solves the technical problem of poor detection effect of micro-wave single-photon detection in the related art.

The present invention provides a silicon-based integrated quantum chip, preparation and testing method, which integrates superconducting nanowires above silicon waveguides, so that the superconducting nanowires and silicon waveguides form evanescent wave coupling through a silicon oxide covering layer, and waveguide-coupled on-chip single-photon detection can be realized; a higher evanescent wave absorption rate can be achieved through the silicon oxide covering layer located between the superconducting nanowires and the silicon waveguide, and the silicon oxide covering layer can act as a mask when growing superconducting nanowires to avoid damaging the silicon waveguide, so as to reduce the loss of the silicon waveguide; the silicon oxide covering layer with a smaller surface roughness after CMP can ensure the flatness of the superconducting nanowires, so as to reduce dark counts and improve quantum performance; a multi-channel silicon-based integrated quantum chip can be prepared. The present invention can achieve integration and scale, and reliably maintain the processing capability of high-fidelity single-photon signals.

The present invention discloses a QKD optical pulse timing synchronization correction system, which includes a photoelectric conversion and signal processing module, a frequency doubling processing module, an optical pulse timing synchronization correction circuit, an optical box, a detection module and a main control unit; the photoelectric conversion and signal processing module, the frequency doubling processing module and the optical pulse timing synchronization correction circuit are connected in sequence; the optical box, the detection module and the main control unit are connected in sequence; the output port of the optical pulse timing synchronization correction circuit is connected to the detection module, and the main control unit controls the optical pulse timing synchronization correction circuit; the detection module receives a gate signal and identifies a single photon signal, and at the same time inputs the detected single photon count value into the main control unit for sampling, and the main control unit determines whether the count value is a maximum value: if it is a maximum value, the count value is stored; if it is not a maximum value, the main control unit controls the optical pulse timing synchronization correction circuit to continue to search for the maximum count value. The present invention can minimize dark counts on the one hand, and ensure that Bob's receiving end obtains the maximum count detection photon on the other hand.

The present invention discloses a photodiode and a TOF distance measuring device, wherein the photodiode comprises a substrate, a first electrode layer, a first electrode, a second electrode layer, a second electrode and an auxiliary electrode, wherein the first electrode layer is arranged on the substrate, the first electrode is arranged on the first electrode layer, the second electrode is arranged on the substrate, the second electrode is arranged on the second electrode layer, and the auxiliary electrode is connected to a potential or suspended to generate an electric field that opposes the direction of the electric field between the first electrode layer and the substrate, or to shield the electric field between the first electrode layer and the substrate. In the photodiode and the TOF distance measuring device of the present invention, since the auxiliary electrode generates an electric field that opposes the direction of the electric field between the first electrode layer and the substrate, or the auxiliary electrode shields the electric field between the first electrode layer and the substrate, the electric field at the edge of the first electrode layer can be reduced, thereby playing a role in reducing dark counts.