The disclosure relates to a quantum detector configured to receive a microwave signal from a microwave source. The quantum detector comprises a main element formed by a main Josephson junction and a Josephson transmission line which is coupled to the main element for outputting a measurement signal. The Josephson transmission line comprises at least a first set of JTL elements and a second set of JTL elements. The capacitively shunted Josephson junction in each JTL element in the first set is weakly damped, and the JTL element in the second set are more strongly damped than the JTL elements in the first set.

A resonator, an oscillator, and a quantum computer in which the area occupied by the circuit can be reduced is provided. A resonator (100) includes a loop circuit (110) in which a first superconducting line (101), a first Josephson junction (103), a second superconducting line (102), and a second Josephson junction (104) are connected in a ring shape, and a capacitor (120). The capacitor (120) and the loop circuit (110) are connected in a ring shape.

A superconducting input and/or output system employs at least one microwave superconducting resonator. The microwave superconducting resonator(s) may be communicatively coupled to a microwave transmission line. Each microwave superconducting resonator may include a first and a second DC SQUID, in series with one another and with an inductance (e.g., inductor), and a capacitance in parallel with the first and second DC SQUIDs and inductance. Respective inductive interfaces are operable to apply flux bias to control the DC SQUIDs. The second DC SQUID may be coupled to a Quantum Flux Parametron (QFP), for example as a final element in a shift register. A superconducting parallel plate capacitor structure and method of fabricating such are also taught.

According to one embodiment, an electronic circuit includes a first current path, a second current path, and a third current path. The first current path includes a first Josephson junction. The second current path includes a second Josephson junction. The third current path includes a plurality of third Josephson junctions. One end of the second current path is electrically connected to one end of the first current path. Another end of the second current path is electrically connected to another end of the first current path. One end of the third current path is electrically connected to the one end of the first current path and the one end of the second current path. Another end of the third current path is electrically connected to the other end of the first current path and the other end of the second current path.

According to one embodiment, a computing device includes a first conductive body, a first element, a second element, a first transmission line and a second transmission line. The first conductive body spreads along a first plane. The first element includes a Josephson junction and is separated from the first conductive body in a direction crossing the first plane. The second element includes a Josephson junction. The second element is separated from the first conductive body in the direction crossing the first plane. A direction from the first element toward the second element is along a first direction along the first plane. The first transmission line generates an electromagnetic field applied to the first element. The second transmission line generates an electromagnetic field applied to the second element.

Provided is a terahertz-band electromagnetic wave oscillation element that includes an independent terahertz wave oscillation unit for oscillating terahertz-band electromagnetic waves. The terahertz wave oscillation unit consists of a discoid superconductor having a multilayered Josephson junction that enables oscillation of the terahertz-band electromagnetic waves by coordinated vibration of a plurality of Josephson junctions using an AC Josephson effect, the superconductor being circular in a cross section parallel to a lamination plane of the multilayered Josephson junction.

A superconducting input and/or output system employs at least one microwave superconducting resonator. The microwave superconducting resonator(s) may be communicatively coupled to a microwave transmission line. Each microwave superconducting resonator may include a first and a second DC SQUID, in series with one another and with an inductance (e.g., inductor), and a capacitance in parallel with the first and second DC SQUIDs and inductance. Respective inductive interfaces are operable to apply flux bias to control the DC SQUIDs. The second DC SQUID may be coupled to a Quantum Flux Parametron (QFP), for example as a final element in a shift register. A superconducting parallel plate capacitor structure and method of fabricating such are also taught.

A tunable oscillator including a Josephson junction. In some embodiments, the tunable oscillator includes a first superconducting terminal, a second superconducting terminal, a graphene channel including a portion of a graphene sheet, and a conductive gate. The first superconducting terminal, the second superconducting terminal, and the graphene channel together may form a Josephson junction having an oscillation frequency, and the conductive gate may be configured, upon application of a voltage across the conductive gate and the graphene channel, to modify the oscillation frequency.

An electromechanical conversion device includes a resonant electrical circuit comprising an inductance and a capacitor, the capacitor including at least a first electrode and a second electrode; and a mechanical oscillator including at least one microbeam formed in a membrane, the first and second electrodes being located side by side and the first electrode of the capacitor being located on a face of the microbeam so that the electrical capacitance of the capacitor varies when the mechanical oscillator oscillates; device wherein the inductance includes an electric track of very low thickness made on the membrane and made of a superconductive material chosen so as to obtain an electric track with a high kinetic inductance.

According to one embodiment, a computing device includes a first conductive body, a first element, a second element, a first transmission line and a second transmission line. The first conductive body spreads along a first plane. The first element includes a Josephson junction and is separated from the first conductive body in a direction crossing the first plane. The second element includes a Josephson junction. The second element is separated from the first conductive body in the direction crossing the first plane. A direction from the first element toward the second element is along a first direction along the first plane. The first transmission line generates an electromagnetic field applied to the first element. The second transmission line generates an electromagnetic field applied to the second element.