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arXiv · 2511.20437

Fast Quantum Gates for Neutral Atoms Separated by a Few Tens of Micrometers

Matteo Bergonzoni·Rosario Roberto Riso·Guido Pupillo
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Abstract

We present a theoretical scheme for a family of fast and high-fidelity two-qubit iSWAP gates between neutral atoms separated by more than 20 um, enabled by resonant dipole-dipole spin-exchange interactions between Rydberg states. The protocol harnesses coherent excitation-exchange-deexcitation dynamics between the qubit and the Rydberg states within a single and smooth laser pulse, in the presence of strong dipole-dipole interactions. We utilize optimal control methods to achieve theoretical gate fidelities and durations comparable to blockade-based gates in the presence of relevant noise, while extending the effective interaction range by an order of magnitude. This enables entanglement well beyond the blockade radius, offering a route toward fast, high-connectivity quantum processors.

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Matteo Bergonzoni, Rosario Roberto Riso, Guido Pupillo. 2025-11-25. Fast Quantum Gates for Neutral Atoms Separated by a Few Tens of Micrometers. https://arxiv.org/abs/2511.20437

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