Subspace benchmarking high-fidelity entangling operations with trapped ions

  title={Subspace benchmarking high-fidelity entangling operations with trapped ions},
  author={C H Baldwin and Bryce J Bjork and J. P. Gaebler and David Hayes and Daniel Stack},
  journal={Physical Review Research},
We present a new and simplified two-qubit randomized benchmarking procedure that operates only in the symmetric subspace of a pair of qubits and is well suited for benchmarking trapped-ion systems. By performing benchmarking only in the symmetric subspace, we drastically reduce the experimental complexity, number of gates required, and run time. The protocol is demonstrated on trapped ions using collective single-qubit rotations and the Molmer-Sorenson (MS) interaction to estimate an entangling… 

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