Strategies for optimizing plasmonic grating couplers with topology-based inverse design

TL;DR

This paper explores the use of topology-based inverse design to optimize plasmonic grating couplers, comparing it with conventional methods and analyzing its impact on device performance and computational efficiency.

Contribution

It demonstrates the application of a commercial inverse design tool to create complex grating couplers and evaluates different design strategies for improved nanophotonic device performance.

Findings

Inverse design produces more compact grating couplers.

Design strategies significantly influence inverse design outcomes.

Limitations of the inverse design tool are identified and discussed.

Abstract

Numerical simulations have become a cornerstone technology in the development of nanophotonic devices. Specifically, 3D finite difference time domain (FDTD) simulations are a widely used due to their flexibility and powerful design capabilities. More recently, FDTD simulations in conjunction with a design methodology called inverse design has become a popular way to optimize device topology, reducing a device's footprint and increasing performance. We implement a commercial inverse design tool to generate complex grating couplers and explore a variety of grating coupler design methodologies. We compare the conventionally designed grating couplers to those generated by the inverse design tool. Finally, we discuss the limitations of the inverse design tool and how different design strategies for grating couplers affect inverse design performance, both in terms of computational cost and performance of the resulting device.