Fast Multichannel Inverse Design through Augmented Partial Factorization

Area of Science:

• Nanophotonics
• Computational electromagnetics
• Metasurface design

Background:

• Computer-automated design has advanced nanophotonic devices.
• Massively multichannel systems (e.g., metasurfaces, photonic circuits) remain challenging for conventional design methods.
• Current methods require numerous simulations (forward and adjoint) for gradient computation.

Purpose of the Study:

• To develop an efficient formalism for the inverse design of massively multichannel nanophotonic systems.
• To overcome the computational bottleneck of conventional simulation-heavy approaches.
• To enable the design of complex optical components with multiple functionalities.

Main Methods:

• Development of a formalism based on the augmented partial factorization method.
• Achieving objective function and gradient computation in a single or few simulations.
• Applying the method to inverse design a metasurface beam splitter.

Main Results:

• Over two orders of magnitude speedup in computation.
• Significant reduction in memory usage.
• Successful inverse design of a metasurface beam splitter for 3D sensing applications.

Conclusions:

• The proposed formalism significantly accelerates the inverse design of massively multichannel nanophotonic systems.
• This method is crucial for developing advanced optical components like metasurface beam splitters.
• Enables efficient design for a broad range of multichannel optical systems.