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arXiv · 1506.06416

A Rydberg blockade CNOT gate and entanglement in a 2D array of neutral atom qubits

K. M. Maller·M. T. Lichtman·T. Xia·Y. Sun·M. J. Piotrowicz·A. W. Carr·L. Isenhower·M. Saffman
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Abstract

We present experimental results on two-qubit Rydberg blockade quantum gates and entanglement in a two-dimensional qubit array. Without post selection against atom loss we achieve a Bell state fidelity of $0.73\pm 0.05$, the highest value reported to date. The experiments are performed in an array of single Cs atom qubits with a site to site spacing of $3.8 ~ \mu\rm m$. Using the standard protocol for a Rydberg blockade C$_Z$ gate together with single qubit operations we create Bell states and measure their fidelity using parity oscillations. We analyze the role of AC Stark shifts that occur when using two-photon Rydberg excitation and show how to tune experimental conditions for optimal gate fidelity.

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K. M. Maller, M. T. Lichtman, T. Xia, Y. Sun, M. J. Piotrowicz, A. W. Carr, L. Isenhower, M. Saffman. 2015-06-21. A Rydberg blockade CNOT gate and entanglement in a 2D array of neutral atom qubits. https://doi.org/10.1103/physreva.92.022336

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