Change energy bands for materials in FDTD


I want to simulate a si solar cells but with different Si materials, such as mono crystal-si, micro c-Si and amorph-si.

In DEVICE I can choose appropriate Eg, mobility, carrier lifetime to model each of above materials.
But, in FDTD how can I have P-abstotal for each one ( absorption spectrum of each one)?
I thought I can do it by changing the Eg of Si, however, it is not possible to do it in FDTD.

Hi @heejae86,

In FDTD we don’t have a material model that captures the dependence of the optical properties (permittivity/index or conductivity) on the band structure (for instance on the energy gap, Eg).

These are some alternatives you can use:

  • Analytical material: If you have a analytical model for the permittivity/index that includes the effect of Eg.
  • Sampled data materials: If you want to consider a few values of Eg and you have n,k data for each of them.