Randomized Benchmarking Protocol for Dynamic Circuits
Dynamic circuit operations -- measurements with feedforward -- are important
components for future quantum computing efforts, but lag behind gates in the
availability of characterization methods. Here we introduce a series of dynamic
circuit benchmarking routines based on interleaving dynamic circuit operation
blocks $F$ in one-qubit randomized benchmarking sequences of data qubits. $F$
spans between the set of data qubits and a measurement qubit and may include
feedforward operations based on the measurement. We identify six candidate
operation blocks, such as preparing the measured qubit in $|0\rangle$ and
performing a $Z$-Pauli on the data qubit conditioned on a measurement of `1'.
Importantly, these blocks provide a methodology to accumulate readout
assignment errors in a long circuit sequence. We also show the importance of
dynamic-decoupling in reducing ZZ crosstalk and measurement-induced phase
errors during dynamic circuit blocks. When measured on an IBM Eagle device with
appropriate dynamical decoupling, the results are consistent with measurement
assignment error and the decoherence of the data qubit as the leading error
sources.
Liran Shirizly Luke C. G. Govia David C. McKay