Rydberg-Mediated Entanglement in a Two-Dimensional Neutral Atom Qubit Array

We demonstrate high fidelity two-qubit Rydberg blockade and entanglement on a pair of sites in a large two-dimensional qubit array. The qubit array is defined by a grid of blue detuned lines of light with 121 sites for trapping atomic qubits. Improved experimental methods have increased the observed Bell state fidelity to FBell=0.86(2). Accounting for errors in state preparation and measurement we infer a fidelity of FBell-SPAM=0.88. Accounting for errors in single qubit operations we infer that a Bell state created with the Rydberg mediated CZ gate has a fidelity of FBell^{CZ}=0.89. Comparison with a detailed error model based on quantum process matrices indicates that finite atom temperature and laser noise are the dominant error sources contributing to the observed gate infidelity.