Figure 2

The quality and entanglement time of selected solutions (sets of quorums) discovered by using Powell’s method with 500 random diverse starting points, for the Heisenberg (a), (b) and the Ising interaction (c), (d) with noise described by the depolarizing channel (a), (c) or over- and under-rotation (b), (d). Only the 10 best solutions are visualized for each noise level. The points with the red circles represent the optimized quorums resulting from using Powell’s method with standard MUBs as starting points being as good as or better than the best results from the exploratory analysis. Here r and ζ are the noise parameters for the over-and-under rotation noise model and for the depolarizing channel, respectively