Towards 3D-Printed Inverse-Designed Metaoptics

TL;DR

This paper introduces a topology optimization framework for designing volumetric 3D metaoptics, enabling multifunctional, high-efficiency optical devices with experimental validation of a 3D-printed light concentrator working at multiple angles.

Contribution

It presents a novel inverse design method for volumetric 3D metaoptics using topology optimization, overcoming limitations of single-layer geometries for multifunctional devices.

Findings

Achieved high-efficiency multifunctionality in few-wavelength thick devices.

Demonstrated a 3D-printed light concentrator working at five different angles.

Validated the design approach experimentally with successful optical performance.

Abstract

Optical metasurfaces have been heralded as the platform to integrate multiple functionalities in a compact form-factor, potentially replacing bulky components. A central stepping stone towards realizing this promise is the demonstration of multifunctionality under several constraints (e.g. at multiple incident wavelengths and/or angles) in a single device -- an achievement being hampered by design limitations inherent to single-layer planar geometries. Here, we propose a general framework for the inverse design of volumetric 3D metaoptics via topology optimization, showing that even few-wavelength thick devices can achieve high-efficiency multifunctionality. We embody our framework in multiple closely-spaced patterned layers of a low-index polymer. We experimentally demonstrate our approach with an inverse-designed 3d-printed light concentrator working at five different non-paraxial angles of incidence. Our framework paves the way towards realizing multifunctional ultra-compact 3D nanophotonic devices.