Learning Forum

[M Z]

Dear all,

I'm trying to use FDTD to get the Directivity patterns of my antenna model(which is 8um high and 3um wide with a sharp tip) .My research area is nonlinear optics. I wanna get the directivity patterns of SHG、UVL and fundamental wave respectively like the below picture with a gaussian beam exciting inside the structure.

I have refered to this case:https://optics.ansys.com/hc/en-us/articles/360034395214-Far-field-directivity-calculations-of-an-antenna

But all official cases are almost based on the dipole source.Could you please tell me :

1.how to get the directivity patterns with gaussian beam exciting

2.how to get the directivity patterns of SHG、UVL and fundamental wave respectively(because I have set the chi2 and chi3, they are basically mixed in the space)

Best regards

[Guilin Sun]

The graph you showed is a polar plot of the directivity, and there is a radiation-type directivity. As you can see from the analysis group, it calculates the top and bottom semi-sheres so you can have abox monitor analysis group and do the same thing even it is a Gaussian illumination.

Since the frequency monitor records data for the given wavelengths, you can specify which wavelength you want the monitor to record data.