45 citations · 147 across the 17 of their papers we have counts for
17 papers
Heralded Leakage Detection with Preserved Computational-State Coherence in a Fixed-Frequency Transmon
Takeaki Miyamura, Zhiling Wang, Peter A. Spring +5
Leakage out of the computational subspace is a major error mechanism in superconducting quantum processors. Detecting leakage without disturbing the encoded quantum information can…
QuBE/Qubex: an integrated hardware-software system for superconducting qubit experiments with broadband control
Akinori Machino, Kazuhisa Ogawa, Takefumi Miyoshi +21
Achieving high-fidelity operation in large-scale superconducting qubit systems requires not only control hardware with broad frequency coverage, low crosstalk, and tight synchroniz…
Ultralow-power coherent qubit control using AQFP logic at millikelvin temperatures
Hiroto Mukai, Akiyoshi Tomonaga, Rui Wang +5
Qubit controllers are essential for scaling superconducting quantum processors, but implementing them at the 10 mK stage of a dilution refrigerator remains challenging due to strin…
Control the qubit-qubit coupling with double superconducting resonators
Hui Wang, Rui Wang, Daichi Sugiyama +5
We experimentally studied the switching off processes in the double-resonator coupler superconducting quantum circuit. In both frequency and time-domain, we observed the variation…
Realisation of a Protected Cat-Qutrit Manifold via Engineered Quantum Tunnelling
Sangil Kwon, Daisuke Hoshi, Toshiaki Nagase +8
Engineering quantum tunnelling in phase space has emerged as a viable method for creating a protected logical qubit manifold with biased-noise properties. A promising approach is t…
Probing instantaneous quantum circuit refrigeration in the quantum regime
Shuji Nakamura, Teruaki Yoshioka, Sergei Lemziakov +8
Recent advancements in circuit quantum electrodynamics have enabled precise manipulation and detection of the single energy quantum in quantum systems. A quantum circuit refrigerat…
Entangling Schrödinger's cat states by bridging discrete- and continuous-variable encoding
Daisuke Hoshi, Toshiaki Nagase, Sangil Kwon +9
In quantum information processing, two primary research directions have emerged: one based on discrete variables (DV) and the other on the structure of quantum states in a continuo…
Spectral Properties of Two Superconducting Artificial Atoms Coupled to a Resonator in the Ultrastrong Coupling Regime
Akiyoshi Tomonaga, Roberto Stassi, Hiroto Mukai +3
We experimentally investigate a superconducting circuit composed of two flux qubits ultrastrongly coupled to a common LC resonator. Owing to the large anharmonicity of the flux qub…
Active Initialization Experiment of Superconducting Qubit Using Quantum-circuit Refrigerator
Teruaki Yoshioka, Hiroto Mukai, Akiyoshi Tomonaga +5
The initialization of superconducting qubits is one of the essential techniques for the realization of quantum computation. In previous research, initialization above 99\% fidelity…
Observation and manipulation of quantum interference in a superconducting Kerr parametric oscillator
Daisuke Iyama, Takahiko Kamiya, Shiori Fujii +9
Quantum tunneling is the phenomenon that makes superconducting circuits "quantum". Recently, there has been a renewed interest in using quantum tunneling in phase space of a Kerr p…
Mitigation of noise in Josephson parametric oscillator by injection locking
Gopika Lakshmi Bhai, Hiroto Mukai, Jaw-Shen Tsai
Injection locking is a well-established technique widely used in optics as well as solid-state devices for efficient suppression of noise. We present the spectroscopic characteriza…
Noise properties of a Josephson parametric oscillator
Gopika Lakshmi Bhai, Hiroto Mukai, Tsuyoshi Yamamoto +1
We perform the noise spectroscopy of a Josephson parametric oscillator (JPO) by implementing a microwave homodyne interferometric measurement scheme. We observe the fluctuations in…
Ultrastrong tunable coupler between superconducting LC resonators
Takafumi Miyanaga, Akiyoshi Tomonaga, Hikaru Ito +2
We investigate the ultrastrong tunable coupler for coupling of superconducting resonators. Obtained coupling constant exceeds 1 GHz, and the wide range tunability is achieved both…
Quasiparticle tunneling and 1/f charge noise in ultrastrongly coupled superconducting qubit and resonator
Akiyoshi Tomonaga, Hiroto Mukai, Fumiki Yoshihara +1
We report an experimentally observed anomalous doubly split spectrum and its split-width fluctuation in an ultrastrongly coupled superconducting qubit and resonator. From an analys…
Generating time-domain linear cluster state by recycling superconducting qubits
Shotaro Shirai, Yu Zhou, Keiichi Sakata +2
Cluster states, a type of highly entangled state, are essential resources for quantum information processing. Here we demonstrated the generation of a time-domain linear cluster st…
Superconducting Quantum Annealing Architecture with LC Resonators
Hiroto Mukai, Akiyoshi Tomonaga, Jaw-Shen Tsai
We propose a novel architecture for superconducting circuits to improve the efficiency of a quantum annealing system. To increase the capability of a circuit, it is desirable for a…
Pseudo-2D superconducting quantum computing circuit for the surface code: the proposal and preliminary tests
H. Mukai, K. Sakata, S. J. Devitt +4
Of the many potential hardware platforms, superconducting quantum circuits have become the leading contender for constructing a scalable quantum computing system. All current archi…