A photon source includes a photo-pair generator and a detection device. The photo-pair generator is configured to generate a photon-pair in receiving an input signal. A first photon of the photon-pair is output from the photon source via a first optical path. The detection device is configured to receive a second photon of the photon-pair. The detection device includes a transistor that has a semiconducting component that is a source and a drain of the transistor, and a superconducting component that is adjacent to the semiconducting component and is a gate of the transistor. The transistor is configured to transition from an off state to an on state in response a photon being incident upon the detection device.

The disclosed technology generally relates to superconducting devices, and more particularly to superconducting rings, qubits comprising the superconducting rings and methods of coherently coupling flux states of the superconducting rings. In one aspect, a qubit includes a superconducting ring around a hole. The qubit additionally includes an electric field generator adapted for applying an electric field in a plane of the superconducting ring over at least part of the superconducting ring, and a magnetic field generator adapted for applying a magnetic field component orthogonal to the plane of the superconducting ring such that the magnetic field component at least crosses the hole of the ring.

A photon source includes a photo-pair generator and a detection device. The photo-pair generator is configured to generate a photon-pair in receiving an input signal. A first photon of the photon-pair is output from the photon source via a first optical path. The detection device is configured to receive a second photon of the photon-pair. The detection device includes a transistor that has a semiconducting component that is a source and a drain of the transistor, and a superconducting component that is adjacent to the semiconducting component and is a gate of the transistor. The transistor is configured to transition from an off state to an on state in response a photon being incident upon the detection device.

The various embodiments described herein include methods, devices, and systems for fabricating and operating transistors. In one aspect, a transistor includes: (1) a semiconducting component configured to operate in an on state at temperatures above a semiconducting threshold temperature; and (2) a superconducting component configured to operate in a superconducting state while: (a) a temperature of the superconducting component is below a superconducting threshold temperature; and (b) a first current supplied to the superconducting component is below a current threshold; where: (i) the semiconducting component is located adjacent to the superconducting component; and (ii) in response to a first input voltage, the semiconducting component is configured to generate an electromagnetic field sufficient to lower the current threshold such that the first current exceeds the lowered current threshold, thereby transitioning the superconducting component to a non-superconducting state.

The disclosed technology generally relates to superconducting devices, and more particularly to superconducting rings, qubits comprising the superconducting rings and methods of coherently coupling flux states of the superconducting rings. In one aspect, a qubit includes a superconducting ring around a hole. The qubit additionally includes an electric field generator adapted for applying an electric field in a plane of the superconducting ring over at least part of the superconducting ring, and a magnetic field generator adapted for applying a magnetic field component orthogonal to the plane of the superconducting ring such that the magnetic field component at least crosses the hole of the ring.

Electrical devices operating in a range of 273 C. to 100 C. are disclosed. The devices include an insulating substrate. A UO.sub.2+x crystal or oriented crystal UO.sub.2+x film is on a first portion of the substrate. The UO.sub.2+x crystal or film originates and hosts a non-equilibrium polaronic quantum phase-condensate. A first lead on a second portion of the substrate is in electrical contact with the UO.sub.2+x crystal or film. A second lead on a third portion of the surface is in electrical contact with the UO.sub.2+x crystal or film. The leads are isolated from each other. A UO.sub.2+x excitation source is in operable communication with the UO.sub.2+X crystal or film. The source is configured to polarize a region of the crystal or film thereby activating the non-equilibrium quantum phase-condensate. One source state causes the UO.sub.2+X crystal or film to be conducting. Another source state causes the UO.sub.2+x crystal or film to be non-conductive.

Superconducting Meissner effect transistors, methods of modulating, and systems are disclosed. In one aspect a disclosed transistor includes a superconducting bridge between a first and a second current probe, the first and second current probe being electrically connected to a source and a drain electrical connection, respectively and a control line configured to emit a magnetic field signal having signal strength H.sub.sig at the superconducting bridge. In one aspect the emitted magnetic field is configured to break Cooper pairs in the superconducting bridge.

Superconducting Meissner effect transistors, methods of modulating, and systems are disclosed. In one aspect a disclosed transistor includes a superconducting bridge between a first and a second current probe, the first and second current probe being electrically connected to a source and a drain electrical connection, respectively and a control line configured to emit a magnetic field signal having signal strength H.sub.sig at the superconducting bridge. In one aspect the emitted magnetic field is configured to break Cooper pairs in the superconducting bridge.

The various embodiments described herein include methods, devices, and systems for fabricating and operating transistors. In one aspect, a transistor includes: (1) a semiconducting component configured to operate in an on state at temperatures above a semiconducting threshold temperature; and (2) a superconducting component configured to operate in a superconducting state while: (a) a temperature of the superconducting component is below a superconducting threshold temperature; and (b) a first current supplied to the superconducting component is below a current threshold; where: (i) the semiconducting component is located adjacent to the superconducting component; and (ii) in response to a first input voltage, the semiconducting component is configured to generate an electromagnetic field sufficient to lower the current threshold such that the first current exceeds the lowered current threshold, thereby transitioning the superconducting component to a non-superconducting state.

The various implementations described herein include methods, devices, and systems for detecting light. In one aspect, a photodetector device includes: a superconducting wire, and a transistor that includes a semiconducting component and a superconducting component. The superconducting wire is electrically coupled to the superconducting component. The semiconducting component is located adjacent to the superconducting component. The superconducting component is configured to, in response to receiving an input current exceeding a current threshold, transition from a superconducting state to a non-superconducting state and generate heat sufficient to increase a temperature of the semiconducting component from a temperature below a semiconducting threshold temperature to a temperature above the semiconducting threshold temperature.