Fig. 12: Effectiveness of constraint enforcement using QAOA with Zeno dynamics in simulation and hardware experiments.

Distribution of final measurement results obtained from QAOA applied to the equality- (a) and inequality-constrained (b) problem for different numbers of measurements (N). For the equality-constrained problem experiments were executed both with and without quantum conditional logic (QCL). Each column corresponds to a computational basis state (either in-constraint or out-of-constraint), and the columns are ordered by objective value (to the right is better). The circuits were executed on a classical simulator and on the H1-2 quantum device. There is strong agreement between the hardware results and results from noise-free simulation.