139results about "Superconductive amplifiers" patented technology

In an implementation, a tunable traveling wave parametric amplifier (TWPA) includes a T-stage that includes a first DC-SQUID and a first interface inductively communicatively coupled to the first DC SQUID operable to apply a first bias to the first DC SQUID. The T-stage also includes a second DC-SQUID electrically communicatively coupled to the first DC-SQUID in series via a center node, and a second interface inductively communicatively coupled to the second DC-SQUID operable to apply a second bias to the second DC-SQUID. The TWPA also includes a shunting resonator communicatively coupled to the center node via a coupling capacitance. The shunting resonator includes a third DC-SQUID, and a third interface inductively communicatively coupled to the third DC SQUID operable to apply a third bias to the third DC SQUID. The first, second, and third biases are adjustable to improve a bandwidth of the tunable TWPA.

According to an example aspect of the present invention, there is provided a travelling wave parametric amplifier comprising a transmission line comprising therein a plurality of Josephson elements and a plurality of shunt capacitors, and wherein at least some of the shunt capacitors are dispersive capacitors comprising an open-ended, distributed transmission line.

A Floquet mode traveling wave parametric amplifier (TWPA) is disclosed. The Floquet mode TWPA comprises a plurality of stages, where each stage is made up of a nonlinear element and a shunt capacitor. The nonlinear elements may be Josephson junctions, or a combination of series and / or parallel Josephson junctions. The Floquet mode TWPA is designed such that the critical current of the nonlinear elements in each stage is not constant. In some embodiments, the ratio of the largest critical current to the smallest critical current in the Floquet mode TWPA is at least 2:1. In some embodiments, the nonlinear elements with the largest critical current are disposed at or near the input or output of the amplifier. In this way, reflections and backward amplification may be minimized. Further, the TWPA is formed using planar capacitors on a high resistivity substrate, or using low loss parallel plate capacitors.

A system and method are disclosed for a superconducting traveling-wave parametric amplifier (TWPA) with improved control and performance. In a preferred embodiment, the amplifier comprises an integrated array of symmetric rf-SQUIDs in a transmission line structure. A device was fabricated using niobium superconducting integrated circuits, and confirmed predicted performance, with a maximum gain up to 17 dB and a bandwidth of 4 GHz. A similar device can be applied as a low-noise, low-dissipation microwave amplifier for output from a superconducting quantum computer, or as a preamplifier, switch, or frequency converter for a sensitive microwave receiver, or as an output amplifier for a frequency-multiplexed superconducting detector array.

A wide-band Josephson parametric amplifier and method of fabricating the wide-band Josephson parametric amplifier are described. The wide-band Josephson parametric amplifier comprises a substrate, a coplanar waveguide disposed on the substrate having an impedance that varies over a length of the coplanar waveguide, wherein the coplanar waveguide comprises a conductor separated from a first ground plane by a first gap and a second ground plane by a second gap, and a nonlinear resonator disposed on the substrate and coupled to the coplanar waveguide.

A device comprises a superconducting parametric interferometric circuit, which comprises a signal input port and a signal output port, and a first parametric mixing circuit and a second parametric mixing circuit coupled in parallel between the signal input port and the signal output port. The signal input port configured to receive an input signal having a first frequency. The first parametric mixing circuit is configured to convert the input signal to a first output signal having a second frequency, and the second parametric mixing circuit is configured to convert the input signal to a second output signal having the second frequency. The superconducting parametric interferometric circuit is configured to constructively combine the first and second output signals at the signal output port to generate an output signal having the second frequency, and provide isolation of the signal input port from a signal which is present at the signal output port.

The invention provides a Kerr inversion traveling wave parameter amplifier and a preparation method thereof. The method comprises the following steps: depositing a first layer of superconducting material film on a substrate; exposing and etching the first layer of superconducting material film by using laser direct writing, wherein a superconducting material film serving as a bonding welding pad and forming lower polar plates of capacitors in all repetitive units in the Kerr inversion traveling wave parameter amplifier is reserved; preparing Josephson junctions of aluminum in the repetitive units to obtain a conducted superconducting circuit; growing an aluminum oxide dielectric layer; and growing a top conductor layer and etching a pattern.

This application relates to an integrated filtering and amplification device for quantum computing measurement and control, comprising: a device housing, a circuit board, a front-end attenuation component, a front-end bandpass filter component, a microwave amplification component, a rear-end attenuation component, and a rear-end bandpass filter component. The front-end bandpass filter component, the front-end attenuation component, the microwave amplification component, the rear-end attenuation component, and the rear-end bandpass filter component are sequentially connected to the circuit board and are all integrated within the device housing. By integrating a microwave front-end module with a bandpass filter, attenuator, and microwave amplifier, the complexity of external circuitry is greatly reduced. Furthermore, the integrated front-end module is small in size and can be directly integrated into electronic devices, allowing the measurement and control pulses generated from the electronic devices to be directly connected to the dilution refrigerator, greatly simplifying external wiring and improving system reliability.

The superconducting quantum mechanical device includes first, second, third, and fourth Josephson junctions connected in a bridge circuit having first, second, and third resonant eigenmodes. The device also includes first and second capacitor pads. The first and second capacitor pads and the bridge circuit form a superconducting qubit having a resonant frequency corresponding to the first resonant eigenmode. The device further includes first and second resonator sections. The first and second resonator sections and the bridge circuit form a resonator having a resonant frequency corresponding to the second resonant eigenmode. The device also includes a magnetic flux source disposed near the bridge circuit. The magnetic flux source is configured to provide a magnetic flux through the bridge circuit during operation such that, when the third resonant eigenmode is excited, coupling occurs between the first, second, and third resonant eigenmodes.

The invention relates to a microwave signal amplifier comprising a chain of nonlinear inductive dipole elements each forming an asymmetric superconducting loop with Josephson junctions, said chain being arranged between an input of the chain for applying a signal to be amplified and an output of the chain at which an output signal is developed, the amplifier further comprising a controllable magnetic flux generation system for circulating a current in said loops, the amplifier further comprising a first microwave pump and means for coupling said input of the chain to the first pump, the first pump generating through the first coupling means a wave in the chain in the direction from the input to the output of frequency adjusted to transfer power at the frequency of the signal to be amplified.The device further comprises a second microwave pump and a second means for coupling said output of the chain to said second pump, the second pump generating through the second coupling means a wave in the chain in the direction from the output to the input, at a frequency different from that of the first pump and so as to attenuate in said direction from the output to the input the microwaves propagating at the frequency of the signal to be amplified. Figure for the abstract: Fig. 1.

The present disclosure relates to a TWPA device (1) for a quantum computer having a two- band dispersion relation and being configured to implement 3-wave mixing. The TWPA device (1) comprises chained unit cells (ø), each one comprising a nonlinear inductance element (5) and a capacitor (6) connected to a ground (7) thereof. The unit cells (ø) further comprises one of a resonator circuit (8) and periodically modulated input parameters. The two-band dispersion relation is composed of a lower frequency band and an upper frequency band with a frequency-gap in-between. Further, the TWPA device (1) is configured to receive an amplification signal, receive a pump signal at said input (2). The pump signal having a frequency being in said upper frequency band and being at least 2 / 3 of a cut-off frequency of said TWPA device (1), or said pump signal having a frequency being in said lower frequency band, wherein a second harmonic thereof is within said frequency-gap.

A frequency selector for superconducting parametric amplifiers. According to illustrative embodiments, a frequency selector system for superconducting parametric amplifiers may comprise a Josephson traveling wave parametric amplifier (JTWPA) for producing entangled photon pairs at signal frequency and idler frequency, a resonator electrically connected to the JTWPA for tuning the signal frequency and idler frequency to an application frequency, and an inverse diplexer electrically connected to the resonator for separating the signal frequency and the idler frequency. In some embodiments, a frequency selector system for superconducting parametric amplifiers, comprising a Josephson traveling wave parametric amplifier (JTWPA) for producing entangled photon pairs at signal frequency and idler frequency; a resonator electrically connected to the JTWPA for tuning the signal frequency and idler frequency to an application frequency; and a multiplexer electrically connected to the resonator for separating the signal frequency and the idler frequency.

To provide a superconducting device implemented with a surface acoustic wave resonator and a superconducting microwave resonator that are coupled to a Josephson ring modulator, and methods of applications thereof.SOLUTION: A method comprises: receiving, by a microwave Josephson mixer and from a superconducting surface acoustic wave resonator of a superconducting device, a surface acoustic wave signal that comprises one or more phonons that resonate at a first frequency; receiving, by the microwave Josephson mixer and from a superconducting microwave resonator of the superconducting device, a microwave signal that comprises one or more photons that can resonate at a second frequency; and mixing, by the microwave Josephson mixer, the surface acoustic wave signal and the microwave signal on the basis of a microwave control signal received from a microwave source operatively coupled to the microwave Josephson mixer.SELECTED DRAWING: Figure 8

The invention provides a superconducting parameter amplifier and a preparation method thereof, and the superconducting parameter amplifier comprises a Josephson junction array which is used for providing resonance nonlinearity; the ground capacitor is used for impedance matching; the linear cavity is used for phase matching; the coupling capacitor is used for coupling the linear cavity and the Josephson junction array; the first end of the Josephson junction array is connected with a signal source and used for receiving a pumping signal and an input signal, the second end of the Josephson junction array is connected with the first end of the ground capacitor and the first end of the coupling capacitor, the second end of the ground capacitor is grounded, the second end of the coupling capacitor is connected with the first end of the linear cavity, and the second end of the linear cavity is grounded. By optimizing the design and preparation process of the superconducting parameter amplifier, the linear cavity and the coupling structure are effectively improved, and the frequency response range of the superconducting parameter amplifier is greatly expanded, so that the quality of microwave quantum optics and superconducting quantum bit measurement signal processing can be effectively improved.

The present disclosure relates to a frequency multiplexer (1) comprising a first port (2a), a plurality of second ports (2b), each second port (2b) being associated with a specific frequency band and a plurality of signal filtering portions (30, 40, 50, 60) connecting each second port to said first port (2b). Each signal filtering portion (30, 40, 50, 60) is one of a high-pass signal filtering portions (30), low-pass signal filtering portions (40), band-pass signal filtering portions (50), and band-stop signal filtering portion (60). Furthermore, each signal filtering portion (30, 40, 50, 60) comprises chains of superconducting junctions (35, 45, 55, 65).

A traveling-wave parametric amplifier (TWPA) transmission line having an improved bandwidth includes one or more unit cells. Each unit cell includes a capacitor and a Josephson junction connected in series and leading to ground, configured to provide inductance and non-linearity. One or more distributed resonators are coupled to the transmission line. The distributed resonators are configured to (i) use a first harmonic mode of the resonator for resonance phase matching in the transmission line and (ii) prevent the second mode of the resonator from interacting with the intermodulation product of the transmission line.

The present application provides a method and apparatus for determining a superconducting impedance transformation parametric amplifier, a superconducting impedance transformation parametric amplifier, an electronic device, a computer program product, and a computer-readable storage medium, and the method for determining a superconducting impedance transformation parametric amplifier includes the steps of: calculating an impedance value of an impedance transformation line of a superconducting impedance transformation parametric amplifier and a capacitance value of the amplifier based on a wavelength parameter, a gain parameter, and a bandwidth parameter; calculating a linewidth size of a coplanar waveguide of the superconducting impedance transformation parametric amplifier based on the impedance value of the impedance transformation line; calculating a stub size of the superconducting impedance transformation parametric amplifier based on the impedance value of the impedance transformation line and the capacitance value of the amplifier; and determining a structural parameter of the superconducting impedance transformation parametric amplifier based on the linewidth size and the stub size.

The present invention relates to a quantum magnetic field receiving device including a superconducting quantum interference device (SQUID) or a superconducting quantum interference filter (SQIF) and an electrostatic gating circuit configured to apply electrostatic fields to Josephson Junctions of the SQUID or SQIF.

1. A band-pass parametric amplifier comprising a plurality of unit cells, at least one of the unit cells including a first inductor having a first node coupled to a center conductor and a second node coupled to ground, a first capacitor having a first node coupled to the center conductor and a second node coupled to ground, and a second inductor having a first node coupled to the center conductor, wherein the second capacitor has a first node coupled to a second node of the second inductor, and the second capacitor and second inductor are in series with the center conductor.

Provided in the present application are a determination method and apparatus for a superconducting impedance transformation parametric amplifier, a superconducting impedance transformation parametric amplifier, an electronic device, a computer program product and a computer-readable storage medium. The method comprises: based on a wavelength parameter, a gain parameter and a bandwidth parameter, calculating an impedance value of an impedance transformation line of a superconducting impedance transformation parametric amplifier and a capacitance value of the amplifier; based on the impedance value of the impedance transformation line, calculating a linewidth dimension of a coplanar waveguide of the superconducting impedance transformation parametric amplifier; based on the impedance value of the impedance transformation line and the capacitance value of the amplifier, calculating a stub dimension of the superconducting impedance transformation parametric amplifier; and based on the linewidth dimension and the stub dimension, determining structural parameters of the superconducting impedance transformation parametric amplifier.

The invention provides a low-temperature low-noise amplification device. The low-temperature low-noise amplification device comprises a shell, an input matching transmission line box, a first-stage amplifier box and a post-stage amplifier box, wherein the input matching transmission line box, the first-stage amplifier box and the post-stage amplifier box are arranged in the shell; wherein the input matching transmission line box body, the first-stage amplifier box body and the post-stage amplifier box body are detachably connected in sequence through switching sealing heads. In the low-temperature and low-noise amplification device provided by the invention, the input matching transmission line box body, the first-stage amplifier box body and the post-stage amplifier box body are all independent box body structures, and the box bodies are detachably connected through the switching sealing heads. The structural flexibility of the low-temperature and low-noise amplification device is effectively improved, so that the operation complexity of the low-temperature and low-noise amplification device in the testing process is reduced, and the testing efficiency is improved.

According to an example aspect of the present invention, there is provided a travelling wave parametric amplifier comprising a transmission line comprising therein a plurality of Josephson elements and a plurality of shunt capacitors, and wherein at least some of the shunt capacitors are dispersive capacitors comprising an open- ended, distributed transmission line.

The disclosure is towards parametric amplifiers with inductive input coupling for quantum computing systems. One example aspect of the present disclosure is directed to a quantum computing system comprising a first qubit, a first measurement device, and a first amplifier. The first measurement device is configured to generate a first qubit signal corresponding to a first quantum state of the first qubit. The first amplifier is configured to amplify the first qubit signal. The first amplifier comprises a first transmission-line resonator. The first transmission-line resonator provides an inductive reactance for an electrical coupling between the first measurement device and the first amplifier. The inductive reactance for the electrical coupling enables a transmission of the first qubit signal.

One example includes an amplifier system. The system includes an input configured to receive an input pulse, a first input path coupled to the input and configured to provide the input pulse to a control node, and a second input path coupled to the input and comprising at least one delay element to provide a delayed version of the input pulse to the control node. The system also includes a first amplifier device comprising the control node and being configured to provide a control flux in response to the input pulse and in response to the delayed version of the input pulse. The system further includes a second amplifier device coupled to the first amplifier device, the second amplifier device being set to a flux state in response to the control flux to provide an output voltage.

[Problem] To provide a magnetic flux-type superconducting quantum circuit element that has a practically tolerable anharmonicity and enables densification by avoiding addition of a shunt capacitor, thereby achieving an increased coherence time, and a superconducting quantum computer in which the element is used. [Solution] The problem is solved by a large-area junction magnetic flux-type superconducting quantum circuit element characterized in that the superconducting quantum circuit element is based on a magnetic flux-type superconducting quantum circuit element which comprises three Josephson junctions for one loop and into which an α junction ratio is introduced such that the area of one Josephson junction among the three Josephson junctions is α (0.3≦α≦0.7) times the area of the other Josephson junctions having an equal area, wherein the junction cross-sectional area of the three Josephson junctions is set to be large at β (2≦β≦200) times the junction cross-sectional area of the basic magnetic flux-type superconducting quantum circuit element while the α junction ratio is maintained, whereby an increased coherence time is achieved.

The present disclosure relates to a TWPA device (1) for a quantum computer having a two- band dispersion relation and being configured to implement 3-wave mixing. The TWPA device (1) comprises chained unit cells (ø), each one comprising a nonlinear inductance element (5) and a capacitor (6) connected to a ground (7) thereof. The unit cells (ø) further comprises one of a resonator circuit (8) and periodically modulated input parameters. The two-band dispersion relation is composed of a lower frequency band and an upper frequency band with a frequency-gap in-between. Further, the TWPA device (1) is configured to receive an amplification signal, receive a pump signal at said input (2). The pump signal having a frequency being in said upper frequency band and being at least 2 / 3 of a cut-off frequency of said TWPA device (1), or said pump signal having a frequency being in said lower frequency band, wherein a second harmonic thereof is within said frequency-gap.

A parametric traveling wave amplifier (200) is disclosed in which the amplifiers include: a co-planar waveguide, in which the co-planar waveguide includes at least one Josephson junction (210) interrupting a center trace (204) of the co-planar waveguide; and at least one shunt capacitor coupled to the co-planar waveguide, in which each shunt capacitor of the at least one shunt capacitor includes a corresponding superconductor trace (214) extending over an upper surface of the center trace of the co-planar waveguide, and in which a gap separates the superconductor trace from the upper surface of the center trace, and in which the co-planar waveguide including the at least one Josephson junction and the shunt capacitor establish a predefined overall impedance for the traveling wave parametric amplifier.

A Josephson traveling wave parametric amplifier (JTWPA) comprising an input for receiving a signal, an output for providing an amplified output of the signal and one or more circuit segments in series between the input and the output and is configured for receiving a pump tone for transferring energy from the pump tone to the signal and to an idler tone. Each of the one or more circuit segments comprises, in series, one or more superconducting nonlinear elements in series, and a first resonator with a first fundamental resonance frequency configured for phase matching the pump tone with the signal and the idler tone and a second resonator with a second fundamental resonance frequency configured for mitigating pump depletion at a frequency corresponding to a higher harmonic of the pump tone with the second fundamental resonance frequency being higher than the first fundamental resonance frequency.