Model Gallery

The Model Gallery features COMSOL Multiphysics model files from a wide variety of application areas including the electrical, mechanical, fluid, and chemical disciplines. You can download ready-to-use models and step-by-step instructions for building the model, and use these as a starting point for your own modeling work. Use the Quick Search to find models relevant to your area of expertise, and login or create a COMSOL Access account that is associated with a valid COMSOL license to download the model files.

Self-Focusing of an Optical Beam

A Gaussian beam is launched into BK-7 optical glass. The material has an intensity-dependent refractive index. At the center of the beam, the refractive index is the largest. The induced refractive index profile counteracts diffraction and actually focuses the beam. Self-focusing is important in the design of high-power laser systems. The model demonstrates 3D nonlinear wave propagation.

Fresnel Equations

A plane electromagnetic wave propagating through free space is incident at an angle upon an infinite dielectric medium. This model computes the reflection and transmission coefficients and compares the results to the Fresnel equations.

Plasmonic Wire Grating

In this model, a plane wave is incident on a wire grating on a dielectric substrate. Coefficients for transmission, reflection, and first order diffraction are computed for different angles of incidence The model is set up for one unit cell of the grating, flanked by Floquet boundary conditions describing the periodicity. As applied, this condition states that the solution on one side of the ...

Beam Splitter

A beam splitter is used to split a single beam of light into two. One way of making a splitter is to deposit a thin layer of metal between two glass prisms. The beam is slightly attenuated within the layer, and split into two paths. In this example, the thin metal layer is modeled using a transition boundary condition which reduces the memory requirements. Losses in the metal layer are also ...

Fabry-Perot Cavity

This is an example of a Fabry-Perot cavity, the simplest optical resonator structure. It is a classical problem in optics and photonics. Two methods are shown for computing the Q-factor. The losses in this model are purely via radiation away from the resonator.

Modeling of Negative Refractive Index Metamaterial

It is possible to engineer the structure of materials such that both the permittivity and permeability are negative. Such materials are realized by engineering a periodic structure with features comparable in scale to the wavelength. It is possible to model both the individual unit cells of such a material, as well as, to model to properties of a bulk negative index material. This example ...

Second Harmonic Generation from a Gaussian Beam

It is possible to generate harmonics that are multiples of the frequency of laser light by using nonlinear optical materials. This model demonstrates second harmonic generation using transient wave simulation and nonlinear material properties. A YAG (lambda=1.06 micron) laser beam is focused on a nonlinear crystal so that the waist of the beam is inside the crystal.

Step Index Fiber Bend with Bending Loss

A step index fiber bent into 1cm radius is analyzed with respect to propagating modes and radiation loss. It is shown how to find the power averaged mode radius and how to use this to compute the effective mode index.

Defining a Mapped Dielectric Distribution of a Metamaterial Lens

In this example, the properties of an engineered metamaterial are modeled by a spatially varying dielectric distribution. Specifically, a convex lens shape is defined via a known deformation of a rectangular domain. The dielectric distribution is defined on the undeformed, original rectangular domain and is mapped onto the deformed shape of the lens. Although the lens shape defined here is ...

Transverse Modes for a Symmetric Laser Cavity

This model demonstrates how a nonlinear equation system can be setup to solve for the eigenfrequencies of a symmetric laser cavity. The model uses the bidirectional formulation of the Electromagnetic Waves, Beam Envelopes physics interface. The computed eigenfrequencies are verified with values from analytical expressions.

Quick Search

11 - 20 of 20 First | < Previous | Next > | Last