The settings in the “Advanced Options” tab contains settings that typically do not
need to be adjusted.
Settings include overriding the simulation bandwidth which controls the bandwidth used
to determine the default wavelength range used for material fitting, the range over
which frequency domain monitors record data, and mesh generation when using the auto non-uniform
or custom non-uniform mesh type.
Overriding the simulation bandwidth to include a larger range than the source bandwidth can
be done if simulating nonlinear materials, for example for a second harmonic generation
where there will be light generated outside of the source wavelength range.
You can also override the bandwidth used just for the mesh generation.
This is useful if you are performing a parameter sweep where you are sweeping the source wavelength
and you want the mesh to remain constant for each simulation in the sweep.
Simulation auto shutoff options can also be set in the “Advanced options” tab.
By default, the simulation will automatically end once the auto shutoff level either falls
below 1e-5, or rises above 1e5.
The auto shutoff level gives a measure of the fraction of energy remaining in the simulation
region compared to the energy injected.
If the energy falls below the minimum threshold this indicates that the fields have fully
decayed so there is no reason to continue running the simulation further and ending
the simulation at this point reduces the simulation time.
If the energy rises above the maximum value then this indicates that there could be some
numerical instability which is causing the field amplitudes to diverge towards infinity.
In this case, the simulation will terminate and a warning message will be displayed to
let the user know that the simulation diverged.
This message also includes a link to instructions for modifying the simulation settings in order
to fix the divergence.
It is possible to adjust the minimum and maximum threshold values for the auto shutoff to be
triggered, or turn off the auto shutoff so that the simulation will run for the maximum
simulation time regardless of the auto shutoff level.
The auto shutoff will also be discussed further in the Result Analysis section later in this
For detailed definitions of the settings in the “Advanced options” tab, refer to the
Knowledge base page linked below.