This code provides a 3D simulator for the interaction of ultrafast optical pulses with nanoantenna structures. Calculations include near fields, reflectivity, and transmissivity. The current assumption is that the antennas are laid out in a periodic array.
The code uses standard Python packages along with MEEP for Python.
The most important files included in this package are described briefly below.
Core Python script for running the simulation. This can be called from the command line with an input that lets the script know where to find the appropriate settings yaml file and how to name the output files, as well as flags for controlling the simulation.
This houses an example_settings.yaml file that is complete and can be modified for your own simulation. The suggested way to perform simulations would be to make directories for each set of simulations, and execute from there using a local settings file so that you can keep track of all important settings used for every simulation that you perform.
A compilation of notes and changes to the program for reference.
These scripts assume that the user has the following tools and packages installed.
- Python 3
- Numpy
- Scipy
- Meep
The most straightforward way to run this code is to use Anaconda as the Python management package. From there, Anaconda can be used to install Numpy, Scipy, and MEEP.
Numpy and Scipy are standard packages.
MEEP install instructions can be found here.
Create a settings file in the working directory. The file should be named with the convention NAME_settings.yaml. You can see the /example/example_settings.yaml provided as a starting point.
From the working directory, then call python to execute the script. For example, with for NAME_settings.yaml:
python /PATH/TO/smith_purcell_simulator.py NAME FLAGS
This will run the simulation, using the prefix NAME prepended to all output files so you can track the simulations to the outputs. The FLAGS arguments are used to control how the simulation is to be run. You need to run a background simulation first before simulating the entire structure (see the Flags section below for how to do this).
If you are running the MPI-enabled version of MEEP you can use multiple cores as follows:
mpirun -np N python /PATH/TO/smith_purcell_simulator.py NAME FLAGS
where N is the number of cores to use.
All outputs are in either .mat or .h5 format. These can be used with most standard visualization tools in MATLAB, Python, Octave, etc.
Indicates to run a background reference simulation.
This removes the structure and runs the fields so that in post-processing the proper power transmissivities and reflectivities can be calculated, and a reference for field enhancements can be appropriately defined.
You must run the simulation with this flag at least once before running the full simulation or else there will be errors in reflectivity calculation.
Indicates visualization mode. Replaces materials with numerical epsilons for visualizing the generated structure.