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arXiv · 2408.16274

High-fidelity and robust controlled-Z gates implemented with Rydberg atoms via echoing rapid adiabatic passage

Ming Xue·Shijie Xu·Xinwei Li·Xiangliang Li
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Abstract

High-fidelity and robust quantum gates are essential for quantum information processing, where neutral Rydberg atoms trapped in optical tweezer arrays serving as a versatile platform for the implementation. We propose a rapid adiabatic passage (RAP) scheme for achieving a high-fidelity controlled-Z (CZ) gate on a neutral atom Rydberg platform. Utilizing only global laser dressing, our scheme involves echoing two identical RAP pulses within the Rydberg blockade regime to realize a CZ gate and can be readily extended to a C$^k$Z gate with additional qubits. We predict a CZ gate with fidelity over 0.9995 using akali-atom parameters, and a CCZ gate with fidelity exceeding 0.999. Moreover, the direct utilization of echoing RAP pulses enables the implementation of a four-bit CCCZ gate at fidelity over 0.996 without further optimization. The proposed scheme, remarkably robust to variations in driving fields and realistic decoherence effects, holds promise for future quantum information processing applications.

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Ming Xue, Shijie Xu, Xinwei Li, Xiangliang Li. 2024-08-29. High-fidelity and robust controlled-Z gates implemented with Rydberg atoms via echoing rapid adiabatic passage. https://doi.org/10.1103/physreva.110.032619

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