Hi everyone. This is a quick tutorial on how to import experimental material data for optical simulations.
This tutorial is relevant for Lumerical optical solvers, FDTD Solutions and MODE Solutions.
For optical simulations, defining the correct material properties is crucial for
getting the correct simulation results.
For optical simulations, this means that we need to define the real and imaginary
part of the refractive index or permittivity as a function of wavelength or frequency.
In order to attain results that match well with experimental
measurements, it's always a good idea to use material properties that most
closely resemble the experimental conditions. For example, when calculating
a scattering cross-section of a silver Mie sphere, the result can be very dependent
on material properties. Here you can see that for silver, the refractive index is
actually quite different depending on which reference you choose and this is
why it's always a good idea to use the data that most closely matches your
experimental conditions. So let's see how we can do this in FDTD Solutions. First I
need a file that contains the experimental data. So you can see here,
this file has three columns: the first is in wavelength, units of nanometers, the
second and third columns are the real and imaginary part of my refractive index.
And now in the software, I want to start by clicking on the material database. I'm
going to click on the Add button and add a sample data, and I'm gonna call this
sample data, new material. Here I can click on import data,
and I'm going to select the text file that contains the experimental
measurements. I'm going to make sure that I'm using the right units for wavelength
and I'm using the index. Here I can check that my data has been imported
properly. You can now see this new material with the right data. Next I
also want to go to the material Explorer, and I want to make sure that the
material I just added is imported correctly. So I'm going to select the new
material, I'm going to set the simulation bandwidth that I want and I can click on
fit and plot. Here you can see that the green dots are the material data I just
imported, so here's the real and the imaginary part, and the blue line is what
the FDTD simulation actually uses. So I want to make sure that the fitting is
good. I can close it and once we've verified that the material is imported
correctly, I can now set any object to use this material by going into the
material tab, and under the material drop-down menu I should be able to see
my new material. For more information on how to define
material models for optical simulations please visit the following links on our
website. If you have any type of questions please feel free to contact
support at Lumerical.com. from our website, you can also download a free
30-day trial of any of Lumerical products to see how they can address
your simulation needs.