where α = 0.9 and D * 1 = 9.8 × 10 -3 . A similar condition as in Eq. 2 is applied to advance the SA algorithm for minimizing diffusivity, except the diffusivities are replaced by their negative values. The total number of cycles (k max ) in the SA algorithms used to maximize and minimize diffusivity were 50 and 100, respectively. 2500 steps of the SA algorithm were performed for each cycle. To ensure that microstructures from different domains of the structural landscape were screened, we performed 10 independent runs for both SA algorithms with a different initial morphology for each run, generated using the RSA algorithm.