When to use Ansys Lumerical DGTD — Lesson 2

When to use DGTD

In this video lesson, you will learn about typical applications where using the DGTD solver has an advantage over FDTD.

Alternate video link.

Application Examples

The DGTD can be used for a variety of applications as shown below:

Mie scattering

This example examines light scattering in three dimensions from a gold nano-particle as a result of the Mie scattering phenomenon and compares the scattering and absorption cross-sections of the particle to the analytic solution. We will work on this example as part of the My First Simulation section.

Nanobeam grating

This example demonstrates how to use the DGTD solver to compute the diffraction efficiency and deflection angles of a periodic grating consisting of an array of sub-wavelength silicon beams on top of a glass substrate. This type of grating is used to steer a beam of light by carefully controlling the separation and width of the silicon beams.

Chromatic Polarizer

This example demonstrates the simulation of a chromatic plasmonic polarizer used for color filtering and polarimetry to show the variation in the transmission spectrum as a function of polarization and the position of the dip in transmission as a function of the arm length of the cross-shaped structures of the array.

Photothermal Heating in Plasmonic Nanostructures

In this example, we investigate the effect of photothermal heating in plasmonic nanostructures. Using the DGTD solver for optical simulation and the HEAT solver for thermal simulation, we look at two types of thermo-plasmonic antennae: dipole and diabolo. In this example, we consider arrays of both these antennae under varying optical intensity and compare their performance.

Nanoparticle Scattering

In this example, we construct a complete three-dimensional model of the interaction of a focused optical beam and a perfectly reflecting surface with a nanoparticle. The goal is to determine the minimum feature size of the nanoparticle that results in a strong scattered signal.