Single-modulated-pulse two-qubit gates for Rydberg atoms with noncyclic geometric control

Zi-Yuan Chen; Jia-Hao Liang; Zhao-Xin Fu; Hong-Zhi Liu; Ze-Rui He; 1 Meng Wang; Zhi-Wei Han; Jia-Yi Huang; Qing-Xian Lv; Yan-Xiong Du

arXiv · 2402.01113

Single-modulated-pulse two-qubit gates for Rydberg atoms with noncyclic geometric control

Zi-Yuan Chen·Jia-Hao Liang·Zhao-Xin Fu·Hong-Zhi Liu·Ze-Rui He·1 Meng Wang·Zhi-Wei Han·Jia-Yi Huang·Qing-Xian Lv·Yan-Xiong Du

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Abstract

Arrays of neutral atoms have emerged as promising platforms for quantum computing. Realization of high-fidelity two-qubit gates with robustness is currently a significant important task for large-scale operations. In this paper, we present a convenient approach for implementing a two-qubit controlled-phase gate using Rydberg blockade. We achieve the noncyclic geometric control with a single modulated pulse. As compared with the control scheme by cyclic evolution that determined by dynamical parameters, the robustness of the proposal against systematic errors will be remarkably improved due to the geometric characteristic. Importantly, the noncyclic geometric control reduces the gate time for small rotation angles and will be more insensitive to the decoherence effect. We accelerate the adiabatic control with the aid of shortcuts to adiabaticity to further shorten the operation time. We apply our protocol to the algorithm of quantum Fourier transformation to show the actual acceleration. Therefore, the proposed scheme will provide an analytical waveforms for arbitrary two-qubit gates and may have important use in the experiments of atomic arrays.

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Zi-Yuan Chen, Jia-Hao Liang, Zhao-Xin Fu, Hong-Zhi Liu, Ze-Rui He, 1 Meng Wang, Zhi-Wei Han, Jia-Yi Huang, Qing-Xian Lv, Yan-Xiong Du. 2024-02-02. Single-modulated-pulse two-qubit gates for Rydberg atoms with noncyclic geometric control. https://arxiv.org/abs/2402.01113

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