Individual measurement outcomes of a KCBS test for hidden variables in a superconducting qutrit

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The test was performed on a single superconducting qutrit of the transmon type embedded in a 3d microwave cavity. The state of the qutrit was measured dispersively with a heterodyne detection setup. For each experimental run, the qutrit was first initialised to its ground state by thermalisation, with a success rate of approximately 90%. Runs with failed initialisation were identified by a measurement along |0> and discarded. Initialisation was followed by a pair of two-outcome measurements of observables A_i and A_j, whose outcomes are recorded in the data file. An outcome of -1 indicates a qutrit state along direction |l_i> (|l_j>) associated with the observable, +1 indicates a qutrit state in the subspace perpendicular to |l_i> (|l_j>). Contexts (i, j) = (1, 2), (2, 1), (2, 3), (3, 2), (3, 4), (4, 3), (4, 5), (5, 4), (5, 1), (1, 5) are measured in this order. Diagnostic runs to monitor the parameters of the qutrit and determine a mapping from the analog voltages acquired by the detector to qutrit states were performed after every full set of contexts.