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arXiv · 2206.12171

Spatial dependence of fidelity for a two-qubit Rydberg-blockade quantum gate

Ivan Vybornyi·Leonid Gerasimov·Dmitriy Kupriyanov·Stanislav Straupe·Kirill Tikhonov
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Abstract

We study the spatial performance of the entangling gate proposed by H. Levine et al. (Phys. Rev. Lett. 123, 170503 (2019)). This gate is based on a Rydberg blockade technique and consists of just two global laser pulses which drive nearby atoms. We analyze the multilevel Zeeman structure of interacting $^{87}$Rb Rydberg atoms and model two experimentally available excitation schemes using specific driving beams geometry and polarization. In particular, we estimate the blockade shift dependence on inter-atomic distance and angle with respect to the quantization axis. In addition, we show that using Rydberg $d$-states, in contrast to $s$-states, leads to a pronounced angular dependence of the blockade shift and gate fidelity.

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Ivan Vybornyi, Leonid Gerasimov, Dmitriy Kupriyanov, Stanislav Straupe, Kirill Tikhonov. 2022-06-24. Spatial dependence of fidelity for a two-qubit Rydberg-blockade quantum gate. https://arxiv.org/abs/2206.12171

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