High-NA achromatic metalenses by inverse design

Abstract

We use inverse design to discover metalens structures that exhibit broadband, achromatic focusing across low, moderate, and high numerical apertures. We show that standard unit-cell approaches cannot achieve high-efficiency high-NA focusing, even at a single frequency, due to the incompleteness of the unit-cell basis, and we provide computational upper bounds on their maximum efficiencies. At low NA, our devices exhibit the highest theoretical efficiencies to date. At high NA—of 0.9 with translation-invariant films and of 0.99 with “freeform” structures—our designs are the first to exhibit achromatic high-NA focusing.

Document Details

Document Type
Pub Defense Publication
Publication Date
Feb 24, 2020
Source ID
10.1364/oe.385440

Entities

People

  • Haejun Chung
  • Owen Miller

Organizations

  • Air Force Office of Scientific Research

Tags

Fields of Study

  • Physics

Readers

  • Microwave Engineering.
  • Optical Physics and Photonics.
  • Wave Propagation and Nonlinear Chaotic Dynamics.