Experimental implementation of non-Clifford interleaved randomized
  benchmarking with a controlled-S gate
Hardware efficient transpilation of quantum circuits to a quantum devices
native gateset is essential for the execution of quantum algorithms on noisy
quantum computers. Typical quantum devices utilize a gateset with a single
two-qubit Clifford entangling gate per pair of coupled qubits, however, in some
applications access to a non-Clifford two-qubit gate can result in more optimal
circuit decompositions and also allows more flexibility in optimizing over
noise. We demonstrate calibration of a low error non-Clifford
Controlled-$\frac{\pi}{2}$ phase (CS) gate on a cloud based IBM Quantum
computing using the Qiskit Pulse framework. To measure the gate error of the
calibrated CS gate we perform non-Clifford CNOT-Dihedral interleaved randomized
benchmarking. We are able to obtain a gate error of $5.9(7) \times 10^{-3}$ at
a gate length 263 ns, which is close to the coherence limit of the associated
qubits, and lower error than the backends standard calibrated CNOT gate.
Shelly Garion Naoki Kanazawa Haggai Landa David C. McKay Sarah Sheldon Andrew W. Cross Christopher J. Wood