Superconducting microwave devices Archives - IEEE Transactions on Quantum Engineering

SU(4) Gate Design via Unitary Process Tomography: Its Application to Cross-Resonance-Based Superconducting Quantum Devices

July 3, 2025Michihiko Sugawara; Takahiko SatohPhysical ImplementationsCalibration, Coherence time, Logic gates, Qubit, Resonance, Schedules, Superconducting microwave devices, Systematics, Tensors, Tomography

Abstract: In this article, we present a novel approach for implementing pulse-efficient SU(4) gates on cross resonance (CR)-based superconducting quantum devices. Our method introduces a parameterized unitary derived from the CR-Hamiltonian propagator, which accounts for ZZ-interactions. Leveraging the Weyl chamber’s geometric structure, we successfully realize a continuous two-qubit basis gate, RZZ(θ), as an echo-free pulse […]

Control of a Josephson Digital Phase Detector via an SFQ-Based Flux Bias Driver

June 26, 2025Laura Di Marino; Luigi Di Palma; Michele Riccio; Francesco Fienga; Marco Arzeo; Oleg MukhanovQuantum ComputingDetectors, Integrated circuit modeling, Josephson junctions, Microwave theory and techniques, Noise, Oscillators, Phase detection, Qubit, Superconducting microwave devices, Switches

Abstract: Quantum computation requires high-fidelity qubit readout, preserving the quantum state. In the case of superconductings qubits, readout is typically performed using a complex analog experimental setup operating at room temperature, which poses significant technological and economic barriers to large system scalability. An alternative approach is to perform a cryogenic on-chip qubit readout based on […]

Observing the Poisson Distribution of a Coherent Microwave Field With a Parametric Photon Detector

March 11, 2025Jiaming Wang, Kirill Petrovnin, Pertti J. Hakonen, Gheorghe Sorin ParaoanuQuantum Sensing & MetrologyDetectors, Josephson junctions, Microwave amplifiers, Microwave imaging, Microwave technology, Optical detectors, Photon detectors, Probes, Superconducting microwave devices, Superconducting photodetectors

Abstract: Single-photon detectors are essential for implementing optical quantum technologies, such as quantum key distribution, and for enhancing optical imaging systems such as lidar, while also playing a crucial role in studying the statistical properties of light. In this work, we show how the underlying photon statistics can be revealed by using a threshold detector, […]

Observing the Poisson Distribution of a Coherent Microwave Field With a Parametric Photon Detector

Single-photon detectors are essential for implementing optical quantum technologies, such as quantum key distribution, and for enhancing optical imaging systems such as lidar, while also playing a crucial role in studying the statistical properties of light. In this work, we show how the underlying photon statistics can be revealed by using a threshold detector, implemented […]

Superconducting Through-Substrate Vias on Sapphire Substrates for Quantum Circuits

June 20, 2024Kiyotaka Mukasa, Yusuke Nuruki, Hayato Kubo, Yoshihide Narahara, Motohiro Umehara, Kazuyuki FujieEnabling TechnologiesFilms, Qubit, Substrates, Superconducting films, Superconducting microwave devices, Superconducting transition temperature, Tin

Sapphire substrates have recently been recognized for their potential to improve the coherence time of superconducting qubits. However, due to challenges in via fabrication, silicon substrates have been predominantly used for qubits. In this study, we fabricated vias on sapphire substrates using lasers and deposited TiN films by chemical vapor deposition. Cross-sectional views of the […]

Superconducting Through-Substrate Vias on Sapphire Substrates for Quantum Circuits

June 20, 2024Kiyotaka Mukasa, Yusuke Nuruki, Hayato Kubo, Yoshihide Narahara, Motohiro Umehara, Kazuyuki FujieRegularFilms, Qubit, Substrates, Superconducting films, Superconducting microwave devices, Superconducting transition temperature, Tin

Pulse-Engineered Controlled-V Gate and Its Applications on Superconducting Quantum Device

November 2, 2022Takahiko SatohOpen Access, Quantum ComputingLogic gates, Microwave circuits, Quantum algorithm, Quantum computing, Qubit, Schedules, Superconducting microwave devices

In this article, we demonstrate that, by employing the OpenPulse design kit for IBM superconducting quantum devices, the controlled-V gate ( cv gate) can be implemented in about half the gate time to the controlled-X gate ( cx or cnot gate) and consequently 65.5% reduced gate time compared to the cx -based implementation of cv […]

Qubit-Compatible Substrates With Superconducting Through-Silicon Vias

November 2, 2022K. GrigorasOpen Access, Physical ImplementationsElectrodes, Q-factor, Qubit, Resonators, Semiconductor device measurement, Superconducting microwave devices, Through-silicon vias

We fabricate and characterize superconducting through-silicon vias and electrodes suitable for superconducting quantum processors. We measure internal quality factors of a million for test resonators excited at single-photon levels, on chips with superconducting vias used to stitch ground planes on the front and back sides of the chips. This resonator performance is on par with […]

Quantum Engineering With Hybrid Magnonic Systems and Materials (Invited Paper)

February 8, 2021David D. Awschalom; Chunhui Rita Du; Rui He; F. Joseph Heremans; Axel Hoffmann; Justin Hou; Hidekazu Kurebayashi; Yi Li; Luqiao Liu; Valentine Novosad; Joseph Sklenar; Sean E. Sullivan; Dali Sun; Hong Tang; Vasyl Tyberkevych; Cody Trevillian; Adam W. Tsen; Leah R. Weiss; Wei Zhang; Xufeng Zhang; Liuyan Zhao; Ch. W. Zollitsch.Open Access, Quantum Computer Architecture, Quantum InformationCouplings, Magnetic resonance, Magnetoacoustic effects, Optical sensors, Resonators, Superconducting magnets, Superconducting microwave devices

Quantum technology has made tremendous strides over the past two decades with remarkable advances in materials engineering, circuit design, and dynamic operation. In particular, the integration of different quantum modules has benefited from hybrid quantum systems, which provide an important pathway for harnessing different natural advantages of complementary quantum systems and for engineering new functionalities. […]

High-Fidelity Control of Superconducting Qubits Using Direct Microwave Synthesis in Higher Nyquist Zones

December 8, 2020William D. Kalfus; Diana F. Lee; Guilhem J. Ribeill; Spencer D. Fallek; Andrew Wagner; Brian DonoOpen AccessBandwidth, Hardware, Instruments, Logic gates, Qubit, Radio frequency, Superconducting microwave devices

Control electronics for superconducting quantum processors have strict requirements for accurate command of the sensitive quantum states of their qubits. Hinging on the purity of ultra-phase-stable oscillators to upconvert very-low-noise baseband pulses, conventional control systems can become prohibitively complex and expensive when scaling to larger quantum devices, especially as high sampling rates become desirable for […]