English
Related papers

Related papers: Suppression of static ZZ interaction in an all-tra…

200 papers

Superconducting qubits have achieved remarkable progress in gate fidelity and coherence, yet their typical nearest-neighbor connectivity presents constraints for implementing complex quantum circuits. Here, we introduce a cavity-mediated…

Quantum Physics · Physics 2026-02-10 Shinyoung Hwang , Sangyeon Lee , Eunjong Kim

The implementation of a quantum router capable of performing both quantum signal routing and quantum addressing (a Q2-router) represents a key step toward building quantum networks and quantum random access memories. We realize a Q2-router…

Quantum Physics · Physics 2025-04-07 Connie Miao , Sébastien Léger , Ziqian Li , Gideon Lee , Liang Jiang , David I. Schuster

Quantum dot hybrid qubits exploit an extended charge-noise sweet spot that suppresses dephasing and has enabled the experimental achievement of high-fidelity single-qubit gates. However, current proposals for two-qubit gates require tuning…

Quantum Physics · Physics 2020-01-28 Yuan-Chi Yang , S. N. Coppersmith , Mark Friesen

Superconducting transmon qubits based on hybrid superconductor-semiconductor Josephson junctions (gatemons) offer gate tunability, but their relaxation times remain well below those of state-of-the-art transmons, and the origin of this…

High-fidelity parametric gates have been demonstrated with superconducting qubits via rf flux modulation of the qubit frequency. The modulation however leads to renormalization of the bare qubit-qubit coupling, thereby reducing the gate…

Quantum computation (QC) and simulation rely on long-lived qubits with controllable interactions. Early work in quantum computing made use of molecules because of their readily available intramolecular nuclear spin coupling and chemical…

Crosstalk between target and neighboring spectator qubits due to spillover of control signals represents a major error source limiting the fidelity of two-qubit entangling gates in quantum computers. We show that in our laser-driven…

Quantum Physics · Physics 2022-12-21 Chao Fang , Ye Wang , Shilin Huang , Kenneth R. Brown , Jungsang Kim

For superconducting quantum processors consisting of low anharmonicity qubits such as transmons we give a complete microwave description of the system in the qubit subspace. We assume that the qubits are dispersively coupled to a…

Quantum Physics · Physics 2019-10-23 Firat Solgun , David P. DiVincenzo , Jay M. Gambetta

The transmon, a fabrication-friendly superconducting qubit, remains a leading candidate for scalable quantum computing. Recent advances in tunable couplers have accelerated progress toward high-performance quantum processors. However,…

Noise is a significant obstacle to quantum computing, and $ZZ$ crosstalk is one of the most destructive types of noise affecting superconducting qubits. Previous approaches to suppressing $ZZ$ crosstalk have mainly relied on specific chip…

Quantum Physics · Physics 2022-02-16 Lei Xie , Jidong Zhai , Zhenxing Zhang , Jonathan Allcock , Shengyu Zhang , Yi-Cong Zheng

The cross-resonant gate is an entangling gate for fixed frequency superconducting qubits introduced for untunable qubits. While being simple and extensible, it suffers from long duration and limited fidelity. Using two different optimal…

One of the key challenges in current Noisy Intermediate-Scale Quantum (NISQ) computers is to control a quantum system with high-fidelity quantum gates. There are many reasons a quantum gate can go wrong -- for superconducting transmon…

The inductively shunted transmon (IST) is a superconducting qubit with exponentially suppressed fluxon transitions and a plasmon spectrum approximating that of the transmon. It shares many characteristics with the transmon but offers charge…

Mesoscale and Nanoscale Physics · Physics 2023-07-11 Farid Hassani , Matilda Peruzzo , Lucky N. Kapoor , Andrea Trioni , Martin Zemlicka , Johannes M. Fink

Quantum error correction (QEC) is one of the crucial building blocks for developing quantum computers that have significant potential for reaching a quantum advantage in applications. Prominent candidates for QEC are stabilizer codes for…

The gatemon qubits, made of transparent superconducting-semiconducting Josephson junctions, typically have even weaker anharmonicity than the opaque AlOx-junction transmons. However, flux-frustrated gatemons can acquire a much stronger…

Mesoscale and Nanoscale Physics · Physics 2025-12-17 Shukai Liu , Arunav Bordoloi , Jacob Issokson , Ido Levy , Maxim G. Vavilov , Javad Shabani , Vladimir E. Manucharyan

In conventional transmon qubits, decoherence is dominated by a large number of parasitic two-level systems (TLS) residing at the edges of its large area coplanar shunt capacitor and junction leads. Avoiding these defects by improvements in…

Superconductivity · Physics 2025-09-29 Etienne Daum , Benedikt Berlitz , Steffen Deck , Alexey V. Ustinov , Jürgen Lisenfeld

In the model of gate-based quantum computation, the qubits are controlled by a sequence of quantum gates. In superconducting qubit systems, these gates can be implemented by voltage pulses. The success of implementing a particular gate can…

Quantum Physics · Physics 2017-12-04 D. Willsch , M. Nocon , F. Jin , H. De Raedt , K. Michielsen

High-fidelity two-qubit gates are essential for scalable quantum computing. We present a scheme based on superconducting transmon qubits and a control pulse delivery protocol that enables arbitrary controlled-phase gates modulated solely by…

Accurate and efficient implementation of parallel quantum gates is crucial for scalable quantum information processing. However, the unavoidable crosstalk between qubits in current noisy processors impedes the achievement of high gate…

Quantum Physics · Physics 2026-01-06 Xiaodong Yang , Ran Liu , Jun Li

Sparse connectivity of a superconducting quantum computer results in the large experimental overheads of SWAP gates. In this study, we consider employing a virtual two-qubit gate (VTQG) as an error suppression technique. The VTQG enables a…

Quantum Physics · Physics 2023-05-17 Takahiro Yamamoto , Ryutaro Ohira