Summary
Can a learned RCWA surrogate respect an exact physical constraint?
Projects predicted scattering outputs onto a manifold that enforces energy conservation.
Demonstrates differentiable inverse design for a diffractive waveguide combiner.
Related modelling approaches
Relation labels come from the method guide and are editorial. Unlabelled links are conceptual connections or comparison methods; the paper does not necessarily implement them.
Commentary
The stated model is lossless; its constraint does not transfer unchanged to absorbers or amplifiers.
Physical consistency is valuable, but does not guarantee accuracy for unfamiliar geometry or unresolved resonances.
Interpretation and connections in this note, separate from the authors’ reported findings.