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The materials database and adding new materials

To calculate the photondensity within the device, the model must know the refractive index and absorption of each material layer. This data is stored in, C: $ \backslash$ gpvdm $ \backslash$ materials. The subdirectory name in C: $ \backslash$ gpvdm $ \backslash$ materials identifies the material name. In each sub directory there are two key files alpha.omat and n.omat, these files are standard text files can be opened with any text editor such as wordpad. Alpha.omat contains the absorption coefficient of the material while n.omat contains the the refractive index. The first column of the file contains the wavelength in $ m$ (not $ cm$ or $ nm$ ), and the second column of the file contains the absorption coefficient in $ m^{-1}$ (for alpha.omat) and the real part of the refractive index (i.e. n) in au (for n.omat).

If you wish to add materials to the database which do not come as standard with the model you can do it in the following way: Simply copy an existing material directory (say C: $ \backslash$ gpvdm $ \backslash$ materials $ \backslash$ ito) to a new directory (say C: $ \backslash$ gpvdm $ \backslash$ materials $ \backslash$ mynewmaterial). Then replace alpha.omat and n.omat with your data for the new material. There are two other files in each sub directory, namely fit.inp and mat.inp. The file fit.inp is needed can be ignored, the file mat.inp is defined as follows:


\begin{lstlisting}[language=matlab,frame=single]
...

If you don't have data to hand for your material, but you do have a paper containing the data, you use the program Engauge Digitizer, written by Mark Mitchell https://github.com/markummitchell/engauge-digitizer to export data from publications. After you have finished updating the new material directory, whenever a new simulation is generated the new material files will automatically be copied into the active simulation directory ready for use.


next up previous
Next: Running gpvdm on a Up: Changing the model Previous: Structure of the electrical
rod 2017-12-08