Abstract: Superconducting nanowire single photon detectors have recently been developed for a wide range of applications, including imaging and communications. An improved detection system is disclosed, whereby the detectors are monolithically integrated on the same chip with Josephson junctions for control and data processing. This enables an enhanced data rate, thereby facilitating several new and improved applications. A preferred embodiment comprises integrated digital processing based on single-flux-quantum pulses. An integrated multilayer fabrication method for manufacturing these integrated detectors is also disclosed. Preferred examples of systems comprising such integrated nanowire photon detectors include a time-correlated single photon counter, a quantum random number generator, an integrated single-photon imaging array, a sensitive digital communication receiver, and quantum-key distribution for a quantum communication system.

Abstract: Quantum computing systems require methods to control energies of qubits and couplers for quantum operations. Flux biasing of qubits and quantum couplers is provided for a superconducting quantum computer using single-flux-quantum (SFQ) technology. This method is applicable to a wide range of superconducting qubit structures and couplers, including transmons, fluxoniums, flux qubits, phase qubits and other superconducting qubits. This method enables arbitrary-amplitude time-varying flux biasing of qubits and couplers, due to a sequence of high-speed SFQ pulses. Several preferred embodiments are disclosed which provide high-fidelity control of fast single-qubit and multi-qubit operations.

Abstract: The technology disclosed in this patent document can be implemented to combine quantum computing, classical qubit control/readout, and classical digital computing in a scalable computing system based on superconducting qubits and special interconnection designs for connecting hardware components within a multi-stage cryogenic system to provide fast communications between the quantum computing module and its controller while allowing efficient management of wiring with other modules.

Abstract: Superconducting nanowire single photon detectors have recently been developed for a wide range of applications, including imaging and communications. An improved detection system is disclosed, whereby the detectors are monolithically integrated on the same chip with Josephson junctions for control and data processing. This enables an enhanced data rate, thereby facilitating several new and improved applications. A preferred embodiment comprises integrated digital processing based on single-flux-quantum pulses. An integrated multilayer fabrication method for manufacturing these integrated detectors is also disclosed. Preferred examples of systems comprising such integrated nanowire photon detectors include a time-correlated single photon counter, a quantum random number generator, an integrated single-photon imaging array, a sensitive digital communication receiver, and quantum-key distribution for a quantum communication system.