Optimizing quantum error correction experiments with flux-tunable transmonsPart 1: experiment*

This two-part series presents the optimization of quantum error correction (QEC) experiments on a superconducting quantum processor with 17 flux-tunable transmons. A key experimental obstacle is the presence of two-level systems (TLSs), which can severely compromise the operational fidelities of one- and two-qubit gates as well as readout. In this first part, we implement various calibration strategies to mitigate the impact of TLSs on these building blocks of QEC cycles. We next calibrate and benchmark stabilizer measurements and link physical errors to the temporal and spatial correlation of error detection events. Finally, we show gradual improvement in logical-level fidelity obtained using the progression of error decoders presented in part two.