# Medium
Defines the electromagnetic properties of the structure's medium.
name: User defined medium name.
type: Definition of medium properties.
Options:
# Add Medium
You can add new mediums to your simulation using the following methods:
# New Medium
Click "New Medium", select the model type, and then set the model properties. The ordinary New Medium list contains the optical models. PerturbationMedium and PerturbationPoleResidue are offered when editing a Heat simulation; they are not ordinary FDTD medium choices.
# Material Library
Click "Material Library" and select an existing material from the Public or the Private library.
The public library includes Graphene ("graphene"). Select it from the library to add a graphene medium, then adjust its properties. Graphene is added from the library rather than from the ordinary New Medium list.
# Material Fitter
Click "Material Fitter", upload a refractive index file, and then fit the raw data. See Material Fitter for more details.
# Import Material
Click Import Material and upload a supported medium HDF5 file. The imported medium is validated and displayed in the simulation.
If you prepare the upload outside the editor, create the corresponding medium with the Python interface and call
to_hdf5(filename)(opens new window) to write the expected HDF5 dataset structure. For a spatially varying medium, see the Custom Medium tutorial (opens new window).
# Common Medium Options
Common options appear in Advanced, including the frequency range, Allow_gain, Nonlinearity Specification, and Space-Time Modulation when supported by the selected medium. Face color and transparency are set in the separate Appearance section.
# Thermal Properties
heat_spec: Thermal material specification used by the Heat solver.
Type: FluidSpec or SolidSpec
- Default: SolidSpec for a new medium in a Heat simulation; None otherwise
This section appears when the task group includes a Heat solver and is omitted from a standalone FDTD task.
For the choices, fields, units, defaults, and constraints, see Thermal Properties.
# Related Content:
- Mediums Tutorial (opens new window)
- Modeling dispersive materials (opens new window)
- Fitting dispersive material models (opens new window)
- Defining fully anisotropic materials (opens new window)
- Defining gyrotropic materials (opens new window)
- Defining spatially-varying dielectric structures (opens new window)
- Thermally tuned waveguide (opens new window)