Provided is a dual-band resonator which can be downsized further than conventional ones. A dual-band resonator is provided with a first conductor and a second conductor. The first conductor is configured to be folded at a first folding part at the center so that both extensions are in a prescribed direction and adjacent to one another with a prescribed space therebetween, wherein a conductor part closer to one end side than the first folding part and a conductor part closer to the other end side than the first folding part are further folded at second folding parts between the one end and the first folding part and between the other end and the first folding part, respectively, in a direction in which the one end and the other end are apart from each other. The second conductor extends in a prescribed direction contiguously to the first folding part of the first conductor. The first conductor constitutes a half-wavelength resonator, and odd-mode resonance occurs in the first conductor. The first conductor and the second conductor constitute a half-wavelength resonator, and even-mode resonance occurs in the first conductor and the second conductor.

An apparatus and method for implementing a compact and tunable microwave resonator using NbN kinetic inductance, comprising: a DC source, an attenuator, an oxygen-free copper cavity, a superconducting coil, a first-stage amplifier, a second-stage amplifier, a vector network analyzer and a control computer, a small-sized tunable resonator whose size is reduced by 10-20 times as compared with an ordinary thin film microwave resonator is implemented in a microwave frequency band by using high kinetic inductance of an ultra-thin NbN thin film in a superconducting state, the tunability of the resonator lies in that the ultra-thin NbN thin film serves as the LC resonance circuit, a dc-SQUID is connected to the end of the resonator, and a change in the external magnetic field causes a change in the equivalent inductance of the dc-SQUID, thereby changing the total inductance of the resonator and modulating the resonant frequency of the resonance circuit.

The present disclosure relates to an oscillator apparatus comprising a differential transmission line forming a closed loop, a plurality of active core components that are electrically connected to the differential transmission line and that are configured to compensate for loss in the differential transmission line, a plurality of tuning elements that are electrically coupled with the differential transmission line, and a processor configured to control each tuning element of the plurality of tuning elements to activate or deactivate such that an effective electrical length of the differential transmission line is changed.

A tunable coupler for making a controllable coupling to at least a first qubit is disclosed. The tunable coupler includes a first constant coupling element and a tunable coupling element. The first constant coupling element forms a non-galvanic coupling interface to at least the first qubit at a first extremity that is distant from the tunable coupling element. The tunable coupling element is located adjacent to a non-galvanic coupling interface formed as an interface to a circuit element at a second extremity thereof.

A superconducting coupling device includes a resonator structure. The resonator structure has a first end configured to be coupled to a first device and a second end configured to be coupled to a second device. A gate is positioned proximal to a portion of the resonator structure. The gate is configured to receive a gate voltage and vary a kinetic inductance of the portion of the resonator based upon the gate voltage. The varying of the kinetic inductance induces the resonator structure to vary a strength of coupling between the first superconducting device and the second superconducting device.

Circuitry comprising: a first resonant radio frequency conductive path between a first node and a third node; a second resonant radio frequency conductive path between a second node and the third node; an internode radio frequency conductive path between the first node and the second node; a shunt resonant element coupled to the third node and shared by the first resonant radio frequency conductive path and the second resonant radio frequency conductive path; and a phase shift element for introducing a relative phase shift to the first resonant radio frequency conductive path relative to the second resonant radio frequency conductive path.

Embodiments provide a filtering device, to effectively simplify assembly and tuning processes. The filtering device includes: a housing, including an inner cavity; a resonant conductor, having a resonance function, and disposed inside the inner cavity; and a pressing element, having one end disposed on the housing and another end suspended, and facing a position of an open-circuit end of the resonant conductor. A distance between the pressing element and the resonant conductor is changeable when the pressing element is pressed or drawn to adjust a resonant frequency. The filtering device provided in various embodiments is applicable to a plurality of communications devices for selecting a signal frequency.

A device includes: a substrate; a first superconductor layer on the substrate, the first superconductor layer having a first kinetic inductance; and a second superconductor layer on the first superconductor layer, the second superconductor layer having a second kinetic inductance that is lower than the first kinetic inductance, in which the second superconductor layer covers the first superconductor layer such that the second superconductor layer and the first superconductor layer have a same footprint, with the exception of at least a first region where the second superconductor layer is omitted so that the first superconductor layer and the second superconductor layer form a circuit element having a predetermined circuit parameter.

A six-pole patch bandpass filter includes a dielectric substrate and six electrically-conductive isosceles-triangle patches disposed thereon. A first pair of the patches is an electrically connected pair. The first pair of patches is capacitively coupled to a first microstrip. A second pair of the patches is also an electrically connected pair. The second pair of patches is capacitively coupled to a second microstrip. A third pair of the patches are nested between and capacitively coupled to the first pair of patches and the second pair of patches.

A reflective microstrip tuning circuit that operatively couples to another circuit to be tuned, in which tuning circuit receives an incident signal from the other circuit and enables adjustment of the amplitude and/or phase of the return signal reflected by the tuning circuit for use in the other circuit. The tuning circuit includes one or more cascaded couplers that divide power from the incident signal unequally among a plurality of adjustable tuning arms, in which the tuning arms may be individually adjusted to change the phase of the signal that is reflected by each arm so that both the amplitude and phase of the signal returned by the tuning circuit is adjusted to achieve the desired tuning result. The difference in the power that is divided among the tuning arms provides a progressive weighting to the adjustment effect of each tuning arm, which provides for a series of coarse through fine adjustments that enables a greater degree of resolution when tuning.