Wave Optics Module

For Simulating Electromagnetic Wave Propagation in Optically Large Structures

Wave Optics Module

Directional coupler formed from two interacting waveguides.

Simulating Optical Design Components

The Wave Optics Module provides dedicated tools for electromagnetic wave propagation in linear and nonlinear optical media for accurate component simulation and optical design optimization. With this module you can model high-frequency electromagnetic wave simulations in either frequency- or time-domain in optical structures. It also adds to your modeling of optical media by supporting inhomogeneous and fully anisotropic materials, and optical media with gains or losses. Several 2D and 3D formulations are available in the Wave Optics Module for eigenfrequency mode analysis, frequency-domain, and time-domain electromagnetic simulation. You can calculate, visualize, and analyze your phenomena using postprocessing tools, such as computation of transmission and reflection coefficients.

Analysis for All Types of Optical Media

It is straightforward to simulate optical sensors, metamaterials, optical fibers, bidirectional couplers, plasmonic devices, nonlinear optical processes in photonics, and laser beam propagation. This can be done in 2D, 2D axisymmetric, and 3D spatial domains. Ports can be defined for inputs and outputs, as well as for automatic extraction of S-parameters matrices that contain the full transmission and reflection properties of an optical structure with, potentially, multiple ports. A variety of different boundary conditions can be applied to simulate scattering, periodic, and discontinuity boundary conditions. Perfectly-matched layers (PMLs) are ideal for simulating electromagnetic wave propagation into unbounded, free space while keeping computational costs down. The postprocessing capabilities allow for visualization, evaluation, and integration of just about any conceivable quantity, since you can freely compose mathematical expressions of fields and derived quantities.

事例紹介

  • A Gaussian beam is launched into a BK-7 optical glass, where the refractive index is largest at the center of the fiber, and which counteracts the diffractive effects and actually focuses the beam. The figure indicates a compressed view, and the true aspect ratio of the fiber used in the simulation. A Gaussian beam is launched into a BK-7 optical glass, where the refractive index is largest at the center of the fiber, and which counteracts the diffractive effects and actually focuses the beam. The figure indicates a compressed view, and the true aspect ratio of the fiber used in the simulation.
  • Energy density within a Fabry-Perot cavity over a range of frequencies. With this, you can find the resonant frequencies and Q-factors. Energy density within a Fabry-Perot cavity over a range of frequencies. With this, you can find the resonant frequencies and Q-factors.
  • A gold sphere is illuminated by a plane wave and the scattering is measured. The far-field radiation pattern in the E-plane (blue) and H-plane (green) is shown, along with the resistive heating losses. A gold sphere is illuminated by a plane wave and the scattering is measured. The far-field radiation pattern in the E-plane (blue) and H-plane (green) is shown, along with the resistive heating losses.

A Variety of Tools for Simplifying Optics Simulation

The Wave Optics Module allows for simulation of optical media with inhomogeneous, anisotropic, nonlinear, and dispersive material properties, such as conductivity, refractive index, permittivity, or permeability. To do this, COMSOL Multiphysics gives you access to the relevant 3-by-3 tensor, if your property is anisotropic, or allows you to enter any arbitrary algebraic equations for these material properties for nonlinear, inhomogenous, and dispersive materials. For sweeps over wavelength or frequency, you can define material properties that include expressions in the frequency or wavelength variable. This flexibility in accessing the underlying equations and mathematics that describe the material properties makes the Wave Optics Module perfect for modeling hard-to-describe materials, such as gyromagnetic and metamaterials with engineered properties. It also includes valuable features for simulating Floquet-periodic structures with higher-order diffraction modes, and graded index materials.

Consider the Effects of Other Phenomena on Wave Optics

As with all COMSOL products, the Wave Optics Module seamlessly integrates with COMSOL Multiphysics and the other add-on modules. That integration enables you to couple other physics with the propagation of electromagnetic waves. For instance, you can monitor laser heating, or the effect of structural stresses and deformations on the propagation of light through your optical devices and components.

Accurate Optical Modeling with the Innovative Beam Envelope Method

In time-dependent studies of electromagnetic wave propagation you often assume that all variations in time occur as sinusoidal signals, making the problem time-harmonic in the frequency domain. The Wave Optics Module has a number of interfaces for simulating such phenomena. You can also simulate nonlinear problems where the distortion of the signal is small, thanks to certain features included in the module. If the nonlinear influence is strong, a full time-dependent study of your device is required.

When solving optics propagation problems using traditional methods, a significant number of elements is required to resolve each propagating wave. Small wavelengths are invariably involved when simulating light propagation. Typically, large amounts of computational resources are required when you are modeling components and devices that are large as compared with the wavelength. Instead, the Wave Optics Module approaches these types of simulations using the innovative beam envelope method.

This novel method for electromagnetic full-wave propagation overcomes the need for traditional approximations, by direct discretization of Maxwell’s equations. Here, the electric field is expressed as the product of a slowly varying envelope function and a rapidly varying exponential phase function. This allows for accurate simulations of optically large systems where the geometric dimensions can be much larger than the wavelength, and where light waves cannot be approximated with rays. The conventional electromagnetic full-wave propagation method is also available in the Wave Optics Module, and can be appropriately used in smaller geometries.

Metamaterials Make Physics Seem Like Magic

Surface Plasmon Resonance

A 100-Fold Improvement in Lithography Resolution Realized with a 150-Year-Old “Perfect Imaging” System

Nanorods

Photonic Crystal

Plasmonic Wire Grating

Optical Scattering by Gold Nanospheres

Directional Coupler

Step Index Fiber Bend with Bending Loss

Gaussian Beam Incident at Brewster Angle

Second Harmonic Generation from a Gaussian Beam

Modeling of Negative Refractive Index Metamaterial

Dielectric Slab Waveguide