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arXiv · 2310.19741

Individual-atom control in array through phase modulation

Abstract

Performing parallel gate operations while retaining low crosstalk is an essential step in transforming neutral atom arrays into powerful quantum computers and simulators. Tightly focusing control beams in small areas for crosstalk suppression is typically challenging and can lead to imperfect polarization for certain transitions. We tackle such a problem by introducing a method to engineer single qubit gates through phase-modulated continuous driving. Distinct qubits can be individually addressed to high accuracy by simply tuning the modulation parameters, which significantly suppresses crosstalk effects. When arranged in a lattice structure, individual control with optimal crosstalk suppression is achieved. With the assistance of additional addressing light or multiple modulation frequencies, we develop two efficient implementations of parallel-gate operations. Our results pave the way to scaling up atom-array platforms with low-error parallel-gate operations, without requiring complicated wavefront design or high-power laser beams.

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Guoqing Wang, Wenchao Xu, Changhao Li, Vladan Vuletić, Paola Cappellaro. 2023-10-30. Individual-atom control in array through phase modulation. https://arxiv.org/abs/2310.19741

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