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Related papers: Gradiometric, Fully Tunable C-Shunted Flux Qubits

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We experimentally demonstrate a tunable hybrid qubit in a five-electron GaAs double quantum dot. The qubit is encoded in the (1,4) charge regime of the double dot and can be manipulated completely electrically. More importantly, dot…

Mesoscale and Nanoscale Physics · Physics 2016-03-02 Gang Cao , Hai-Ou Li , Guo-Dong Yu , Bao-Chuan Wang , Bao-Bao Chen , Xiang-Xiang Song , Ming Xiao , Guang-Can Guo , Hong-Wen Jiang , Xuedong Hu , Guo-Ping Guo

The \textit{heavy-fluxonium} circuit is a promising building block for superconducting quantum processors due to its long relaxation and dephasing time at the half-flux frustration point. However, the suppressed charge matrix elements and…

Implementation of high-fidelity two-qubit operations is a key ingredient for scalable quantum error correction. In superconducting qubit architectures tunable buses have been explored as a means to higher fidelity gates. However, these…

With the long coherence time, the fixed-frequency transmon qubit is a promising qubit modality for quantum computing. Currently, diverse qubit architectures that utilize fixed-frequency transmon qubits have been demonstrated with…

Quantum Physics · Physics 2022-06-29 Peng Zhao , Teng Ma , Yirong Jin , Haifeng Yu

We propose a experimentally feasible scheme to demonstrate the geometric phase in flux qubits by means of detuning coherent microwave pulse techniques. Through measuring the probability of the persistent current state in flux qubits, one…

Superconductivity · Physics 2007-05-23 Z. H. Peng , M. J. Zhang , D. N. Zheng

Extremely long coherence times, excellent single-qubit gate fidelities and two-qubit logic have been demonstrated with silicon metal-oxide-semiconductor spin qubits, making it one of the leading platforms for quantum information processing.…

Mesoscale and Nanoscale Physics · Physics 2020-01-14 H. G. J. Eenink , L. Petit , W. I. L. Lawrie , J. S. Clarke , L. M. K. Vandersypen , M. Veldhorst

A flux qubit can have a relatively long decoherence time at the degeneracy point, but away from this point the decoherence time is greatly reduced by dephasing. This limits the practical applications of flux qubits. Here we propose a new…

Superconductivity · Physics 2009-11-11 J. Q. You , Xuedong Hu , S. Ashhab , Franco Nori

Graphene quantum dots are attractive candidates for solid-state quantum bits. In fact, the predicted weak spin-orbit and hyperfine interaction promise spin qubits with long coherence times. Graphene quantum dot devices have been extensively…

Tunable Josephson harmonics open new avenues for qubit design. We demonstrate a superconducting circuit element consisting of a tunnel junction in series with a SQUID loop, yielding a Josephson potential whose harmonic content is strongly…

The fluxonium qubit is a promising candidate for quantum computation due to its long coherence times and large anharmonicity. We present a tunable coupler that realizes strong inductive coupling between two heavy-fluxonium qubits, each with…

Encoding quantum information in quantum states with disjoint wave-function support and noise insensitive energies is the key behind the idea of qubit protection. While fully protected qubits are expected to offer exponential protection…

Semiconductor quantum dots in silicon are promising qubits because of long spin coherence times and their potential for scalability. However, such qubits with complete electrical control and fidelities above the threshold for quantum error…

Mesoscale and Nanoscale Physics · Physics 2016-03-23 Clement H. Wong

In the endeavour to make quantum computers a reality, integrated superconducting circuits have become a promising architecture. A major challenge of this approach is decoherence originating from spurious atomic tunneling defects at the…

Quantum Physics · Physics 2023-03-31 Jürgen Lisenfeld , Alexander Bilmes , Alexey V. Ustinov

We propose to implement tunable interaction of superconducting flux qubits with cavity-assisted interaction and strong driving. The qubits have a three-level Lambda configuration, and the decay of the excited state will be greatly…

Quantum Physics · Physics 2016-01-26 Zheng-Yuan Xue , Ya-Fei Li , Jian Zhou , Yu-Mei Gao , Gang Zhang

Quantum annealing is an optimization technique which potentially leverages quantum tunneling to enhance computational performance. Existing quantum annealers use superconducting flux qubits with short coherence times, limited primarily by…

With superconducting transmon qubits --- a promising platform for quantum information processing --- two-qubit gates can be performed using AC signals to modulate a tunable transmon's frequency via magnetic flux through its SQUID loop.…

Single flux quantum pulses are a natural candidate for on-chip control of superconducting qubits. We show that they can drive high-fidelity single-qubit rotations---even in leaky transmon qubits---if the pulse sequence is suitably…

Quantum Physics · Physics 2016-09-07 Per J. Liebermann , Frank K. Wilhelm

High-performance two-qubit gates have been reported with superconducting qubits coupled via a single-transmon coupler (STC). Most of them are implemented for qubits with a small detuning since reducing residual $ZZ$ coupling for highly…

Quantum Physics · Physics 2023-02-09 Kentaro Kubo , Hayato Goto

Frequency tunable qubit plays a significant role for scalable superconducting quantum processors. The state-of-the-art room-temperature electronics for tuning qubit frequency suffers from unscalable limit, such as heating problem, linear…

Controlling the energy spectrum of quantum-coherent superconducting circuits, i.e. the energies of excited states, the circuit anharmonicity and the states' charge dispersion, is essential for designing performant qubits. This control is…