# Topology Optimized Multi-layered Meta-optics

## TL;DR

This paper introduces a topology optimization framework for designing complex multi-layered metasurfaces, enabling advanced functionalities like aberration correction and angle-invariant focusing in nanophotonics.

## Contribution

It presents a novel topology optimization method that automatically designs multi-layered metasurfaces with enhanced optical functionalities.

## Key findings

- Designed a nanophotonic metalens with angular aberration correction
- Developed an angle-convergent metalens focusing light regardless of incident angle
- Demonstrated complex multi-layered geometries with increased functionalities

## Abstract

We propose a general topology optimization framework for metasurface inverse design that can automatically discover highly complex multi-layered meta-structures with increased functionalities. In particular, we present topology-optimized multi-layered geometries exhibiting angular phase control, including a single-piece nanophotonic metalens with angular aberration correction as well as an angle-convergent metalens that focuses light onto the same focal spot regardless of the angle of incidence.