Learning Forum

[huyhoang.chu]

Dear Lumerical Staff !

I am involved in a project that needs to simulate the measurement result of this paper using Ansys FDTD.
"Surface third and fifth harmonic generation at crystalline Si for non-invasive inspection of Si wafer’s inter-layer defects" 

I want to see how the Third Harmonics intensity changes when the polarization changes with different crystalline orientations and doping. The expected result looks similar to the result from this paper as shown in Figure 1

I tried to run some simple simulations for nonlinear optics from the link below and replace the order susceptibility value by sweeping it with a different polarization angle and plotting the spectrum. The result shows expected tendencies with TH intensity varied with input polarization angle as shown in figure 2. (chi3 was set as 2.45*10^19)

https://optics.ansys.com/hc/en-us/articles/360042190413-Harmonic-generation-with-a-chi2-material

I have several questions as follow:

1. Can I simulate Si with different crystalline orientations? For example, [100] [111]?
2. Can I add different doping conditions to the simulations, like P-type or N-type doping?
3. Does Lumerical have any standard database for the Nonlinear Susceptibility coefficient? 

Hope to hear from you guys soon

Best Regard.

[Guilin Sun]

Good to know you have some satisfied simulation results!

A1: this would be anisotropic, so as long as you have proper refractive indices, you can simulate it. If it is diagonal, simply use them.

if it is a full tensor, you can transform it  https://optics.ansys.com/hc/en-us/articles/360034394694-Creating-anisotropic-optical-materials-in-FDTD-and-MODE

A2:  You can, but you will need either manually calculate the change of refractive index and import them, or you use CHARGE to simulate at different voltage:

np Density and Temperature Index Perturbation - Simulation object

Charge distribution to change in refractive index theory

np density - using 2D CHARGE simulation for 3D FDTD

Material polarization effects in CHARGE simulation

A3: no, unfortunately. Please contact mateial provider, or search online to get some information.