Fast Flux Entangling Gate for Fluxonium Circuits

Chen, Yinqi; Nesterov, Konstantin N.; Manucharyan, Vladimir E.; Vavilov, Maxim G.

doi:10.48550/arxiv.2110.00632

Cited by 11 publications

(12 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We consider these three gates since these are the parameterized versions of the most commonly used entangling gates. Further, the iswap(Θ) and cz(Θ) gates are easily implemented in superconducting circuits using capacitive coupling [29][30][31][33][34][35][36][37]. Note that for Θ = 0,…”

Section: Two-qubit Entangling Gatesmentioning

confidence: 99%

Parameterized Two-Qubit Gates for Enhanced Variational Quantum Eigensolver

Rasmussen¹,

Zinner²

2022

Preprint

View full text Add to dashboard Cite

The variational quantum eigensolver is a prominent hybrid quantum-classical algorithm expected to impact near-term quantum devices. They are usually based on a circuit ansatz consisting of parameterized single-qubit gates and fixed two-qubit gates. We study the effect of parameterized twoqubit gates in the variational quantum eigensolver. We simulate a variational quantum eigensolver algorithm using fixed and parameterized two-qubit gates in the circuit ansatz and show that the parameterized versions outperform the fixed versions for a range of Hamiltonians with applications in quantum chemistry and materials science.

show abstract

Section: Two-qubit Entangling Gatesmentioning

confidence: 99%

Parameterized Two-Qubit Gates for Enhanced Variational Quantum Eigensolver

Rasmussen¹,

Zinner²

2022

Preprint

View full text Add to dashboard Cite

show abstract

“…Because fluxonium spectrum is anharmonic, a strong drive amplitude in that proposal does not cause significant leakage to noncomputational levels, and gate fidelity is therefore not spoiled by shorter coherence times of higher excited states. Another methods to remain in the computational subspace are to implement flux-tunable gates [32][33][34] or tunable couplers [35], although these schemes may incur firstorder flux noise and require added hardware complexity.…”

Section: Introductionmentioning

confidence: 99%

Controlled-NOT gates for fluxonium qubits via selective darkening of transitions

Nesterov¹,

Wang²,

Manucharyan³

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

We analyze the cross-resonance effect for fluxonium circuits and investigate a two-qubit gate scheme based on selective darkening of a transition. In this approach, two microwave pulses at the frequency of the target qubit are applied simultaneously with a proper ratio between their amplitudes to achieve a controlled-not operation. We study in detail coherent gate dynamics and calculate gate error. With nonunitary effects accounted for, we demonstrate that gate error below 10 −4 is possible for realistic hardware parameters. This number is facilitated by long coherence times of computational transitions and strong anharmonicity of fluxoniums, which easily prevents excitation to higher excited states during the gate microwave drive.

show abstract

“…The experimental implementation showed gate fidelity as high as 0.992, limited by the coherence times of the participating non-computational states, which are unprotected [58,59]. Recently, an iSWAP gate [60] between two planar capacitively-coupled fluxoniums was realized by tuning their computational transitions ω 01 's to be onresonant using fast flux, with corresponding gate fidelity as high as 0.997 [61]. The performance of this gate scheme is intrinsically limited by the lower coherence time away from the flux sweet spot, and its operation may involve additional complications such as spectator errors in large-scale devices.…”

Section: Introductionmentioning

confidence: 99%