Optimal Model for Fewer-Qubit CNOT Gates With Rydberg Atoms

Li, Rui; Li, Shurui; Yu, Dongmin; Qian, Jing; Zhang, Weiping

doi:10.1103/physrevapplied.17.024014

Cited by 17 publications

(8 citation statements)

References 77 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The scheme for an arbitrary (n + 1)-qubit Toffoli gate can offer a direct route to multiqubit quantum computation. Upon the basis of one-step implementation to fewerqubit quantum gates by our group [58] this 3D blockadegate scheme can be used to reduce the number of fewerqubit gates, greatly lowering the complexity of quantum device design [19,20]. Other straightforward applications with multiqubit gates are the production of Rydbergmediated entanglement between two atom qubits [59] or within a mesoscopic ensemble of atoms [68], and for fast quantum computation with neutral Rydberg qubits [69] .…”

Section: Discussionmentioning

confidence: 99%

“…This so-called position error could catastrophically break the implementation of Rydberg antiblockade(RAB)-based gates which depend on a severely modified RAB condition [51][52][53][54]. Although the excitation annihilation as reviewed in [55] or transition slow-down [56] effect makes blockade gates benefited from a robustness against interaction fluctuations, most current achievements are still constrained to fewer-qubit gates [14,57,58] because the blockade strength decreases significantly among distant atoms. Here we express the control(target) atom position as r j(t) = r 0,j(t) + δr j(t) (10) where r 0,j = (R ct , θ cjt , φ j ) is obtained by optimization and r 0,t = (0, 0, 0).…”

Section: Resilience To Position Variationsmentioning

confidence: 99%

See 1 more Smart Citation

Multiqubit Toffoli gates and optimal geometry with Rydberg atoms

Yu¹,

Su²,

Jiang³

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Due to its potential for implementing a scalable quantum computer, multiqubit Toffoli gate lies in the heart of quantum information processing. In this article, we demonstrate a multiqubit blockade gate with atoms arranged in a three-dimension spheroidal array. The gate performance is greatly improved by the method of optimization of control-qubit distributions via evolutionary algorithm on the spherical surface, which leads to an enhanced asymmetric Rydberg blockade. This spheroidal configuration, not only arises a well preservation for the dipole blockade energy between arbitrary control-target pairs, which keeps the asymmetric blockade error at a very low level; but also manifests an unprecedented robustness to the spatial position variations, leading to a negligible position error. Taking account of intrinsic errors and with typical experimental parameters, we numerically show that a C6NOT Rydberg gate can be created with a fidelity of 0.9920 which is only limited by Rydberg decays. Our protocol opens up a new platform of higher-dimensional atomic arrays for achieving multiqubit neutral-atom quantum computation.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Resilience To Position Variationsmentioning

confidence: 99%

Multiqubit Toffoli gates and optimal geometry with Rydberg atoms

Yu¹,

Su²,

Jiang³

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…To accelerate pulse optimization we use same Rabi frequency Ω ′ r (t) = Ω r (t). If an effective scheme without the intermediate states |e c,t ⟩ is presumed, the gate operation can even be performed via one excitation laser [56].…”

Section: Theoretical Strategymentioning

confidence: 99%

Proposal for practical Rydberg quantum gates using a native two-photon excitation

Qian

Zhang

2023

Quantum Sci. Technol.

Self Cite

View full text Add to dashboard Cite

Rydberg quantum gate serving as an indispensable computing unit for neutral-atom quantum computation, has attracted intense research efforts for the last decade. However the state-of-the-art experiments have not reached the high gate fidelity as predicted by most theories due to the unexpected large loss remaining in Rydberg and intermediate states. In this paper we report our findings in constructing a native two-qubit controlled-NOT gate based on pulse optimization. We focus on the method of commonly-used two-photon Rydberg excitation with smooth Gaussian-shaped pulses which is straightforward for experimental demonstration. By utilizing optimized pulse shapes the scheme reveals a remarkable reduction in the decays from Rydberg and intermediate states, as well as a high-tolerance to the residual thermal motion of atoms. We extract a conservative lower bound for the gate fidelity \textcolor{black}{$> 0.992$} after taking into account the experimental imperfections. Our results not only reduce the gap between experimental and theoretical prediction because of the optimal control, but also facilitate the connectivity of distant atomic qubits in a larger atom array by reducing the requirement of strong blockade, which is promising for developing multiqubit quantum computation in large-scale atomic arrays.

show abstract

“…According to the frequency range of the external driving field, the resulting longrange resonant (Förster) and off-resonant dipolar (van der Waals) interactions can give rise to Rydberg blockade effect [3][4][5][6][7], Rydberg facilitation (or antiblockade) dynamics [8][9][10][11], and Rydberg dressing mechanism [12][13][14][15][16], which constitute the basic principle for performing most quantum computing and quantum simulation tasks in neutral-atom system . Nevertheless, it should be worth emphasizing that although the above three features have their own advantages for the realization of neutral atomic logic gates in principle, the presence of Rydberg blockade makes it stand out in experimental implementation since the fidelity of such schemes is independent of the large first-order blockade shift [58][59][60][61][62][63][64][65][66][67][68][69][70][71].…”

Section: Introductionmentioning

confidence: 99%

“…Recently, Levine et al improved the traditional gate protocol by selecting a specific detuning parameter of laser light, and the two-qubit controlled-phase gate is carried out in a faster way after two global pulses [66,72]. In addition, compared with the constant-amplitude pulses, the temporal modulation of the laser field is more helpful to avoid unwanted transitions of quantum states and then suppresses the population leakage error [54,67,71,[73][74][75]. Very recently in experiment, Fu et al have achieved the CZ gate with fidelity F = 0.980 (7) after correcting the state preparation and measurement errors using the single-modulated-pulse off-resonant modulated driving [70].…”

Section: Introductionmentioning

confidence: 99%

Single Temporal-Pulse-Modulated Parameterized Controlled-Phase Gate for Rydberg Atoms

Shao

2022

Phys. Rev. Applied

View full text Add to dashboard Cite

We propose an adiabatic protocol for implementing a controlled-phase gate CZ θ with continuous θ of neutral atoms through a symmetrical two-photon excitation process via the second resonance line, 6P in 87 Rb, with a single-temporal-modulation-coupling of the ground state and intermediate state. Relying on different adiabatic paths, the phase factor θ of CZ θ gate can be accumulated on the logic qubit state |11 alone by calibrating the shape of the temporal pulse where strict zero amplitudes at the start and end of the pulse are not needed. For a wide range of θ, we can obtain the fidelity of CZ θ gate over 99.7% in less than 1 µs, in the presence of spontaneous emission from intermediate and Rydberg states. And in particular for θ = π, we benchmark the performance of the CZ gate by taking into account various experimental imperfections, such as Doppler shifts, fluctuation of Rydberg-Rydberg interaction strength, inhomogeneous Rabi frequency, and noise of driving fields, etc, and show that the predicted fidelity is able to maintain at about 98.4% after correcting the measurement error. This gate protocol provides a robustness against the fluctuation of pulse amplitude and a flexible way for adjusting the entangling phase, which may contribute to the experimental implementation of near-term quantum computation and quantum algorithm with neutral-atom systems.

show abstract

Optimal Model for Fewer-Qubit CNOT Gates With Rydberg Atoms

Cited by 17 publications

References 77 publications

Multiqubit Toffoli gates and optimal geometry with Rydberg atoms

Multiqubit Toffoli gates and optimal geometry with Rydberg atoms

Proposal for practical Rydberg quantum gates using a native two-photon excitation

Single Temporal-Pulse-Modulated Parameterized Controlled-Phase Gate for Rydberg Atoms

Contact Info

Product

Resources

About