A Large Angle Deflection Beam Splitter Designed Based on the Method of Moving Asymptotes

Optimum structural design is the process of finding a suitable structure which matches the given parameters and satisfies all constraints. When the objective function is set reasonably, it can be used in nanophotonics to quickly and accurately design a device that meets the requirements. A beam splitter that can split the light wavelengths from 800nm to 1100nm fifty-fifty with 180° separation angle designed by we using a new intelligent design method which combining the moving asymptotes and the finite element method. The fundamental transverse electric (TE) mode of the input ports and output ports. The medium of the device is AMTIR-I and air, and its total efficiency is between 85% to 92%. We also use GaN and air as medium to design the device, its total efficiency has a bit decrease, but still can reach above 83%. This is enough to prove that our algorithm has good universality. The algorithm can be completed with an ordinary personal computer, while the arithmetic speed is quick and the computational complexity is low.