Characterization of addressability by simultaneous randomized benchmarking

Raytheon BBN Technologies, Cambridge, MA 02138, USA(Dated: January 3, 2013)The control and handling of errors arising from cross-talk and unwanted interactions in multi-qubit systems is an important issue in quantum information processing architectures. We introducea benchmarking protocol that provides information about the amount of addressability present in thesystem and implement it on coupled superconducting qubits. The protocol consists of randomizedbenchmarking experiments run both individually and simultaneously on pairs of qubits. A relevantfigure of merit for the addressability is then related to the differences in the measured average gatefidelities in the two experiments. We present results from two similar samples with differing cross-talk and unwanted qubit-qubit interactions. The results agree with predictions based on simplemodels of the classical cross-talk and Stark shifts.