Transformation Inverse Design

Abstract

We present a new technique for the design of transformation-optics devices based on large-scale optimization to achieve the optimal effective isotropic dielectric materials within prescribed index bounds, which is computationally cheap because transformation optics circumvents the need to solve Maxwell's equations at each step. We apply this technique to the design of multimode waveguide bends (realized experimentally in a previous paper) and mode squeezers, in which all modes are transported equally without scattering. In addition to the optimization, a key point is the identification of the correct boundary conditions to ensure reflectionless coupling to untransformed regions while allowing maximum flexibility in the optimization. Many previous authors in transformation optics used a certain kind of quasiconformal map which overconstrained the problem by requiring that the entire boundary shape be specified a priori while at the same time underconstraining the problem by employing "slipping" boundary conditions that permit unwanted interface reflections.

21 pages, 8 figures, submitted to Optics Express, revised 5/22/13 (minor style changes, added references)

References in corpus (4)

• Silicon nanostructure cloak operating at optical frequencies
• Design method for quasi-isotropic transformation materials based on inverse Laplace's equation with sliding boundaries
• Transformation media that turn a narrow slit into a large window
• Transformation bending device emulated by graded-index waveguide

Cited by in corpus (10)

• Outlook for inverse design in nanophotonics
• Intelligent Nanophotonics: Merging Photonics and Artificial Intelligence at the Nanoscale
• Mapping the global design space of nanophotonic components using machine learning pattern recognition
• SUSY-inspired one-dimensional transformation optics
• An all-optical spatial light modulator for field-programmable silicon photonic circuits
• Inverse design of plasma metamaterial devices for optical computing
• Inverse design and experimental realization of plasma metamaterials
• Judiciously distributing laser emitters to shape the desired far field patterns
• Inverse design of plasma metamaterial devices with realistic elements
• Direct manipulation of wave amplitude and phase through inverse design of isotropic media