Metasurface Solves Calculus Problems as Analog Computer

- A lens acts as a Fourier transform on an optical signal.

- d/dx is multiplication by ik in the frequency domain.

- They made a spatial reflection profile r(x) ~ ix using an array of nanobricks of different sizes (optimized with simulation)

- Optical signal -> lens -> reflection from metasurface -> lens = spatial derivative.

I have the paper if anyone wants it and doesn't have access.