Learning Forum

[kai.w.ab]

I ran the simulation with FDTD and nothing remained in the results. I placed a port on a photonic crystal made of silicon from which I excited the basic mode.
I used Python script when setting up the objects.The simulation log contained the following error statement. 

 

 

Error: the source field data for '::port 1 Mode Source' is not valid for the source orientation and dimension.

 

What are the possible causes?

[Guilin Sun]

It is hard to diagnoise here without details of your settings. I would suggest that you manually setup a similar simple device and add the port exactly the same as you are currently using and check if it works. In principle FDTD can have mode source in xy,xz and yz plane without any issue for 3D simulation. Please check your simulation "dimension" to see if it is 2D and you add the mode source in xy plane. Before using advanced method please use simple way to verify the settings. If problem still exists, please post some screen copies here.

[kai.w.ab]

 

 

 

Thank you for your response.

Sorry for asking abstract questions without sending details.

The python script we used for the setup is as follows (I inserted 2d photonic crystals structure as holes in the part that imports the gds files)

 

import numpy as np

import lumapi

fdtd = lumapi.FDTD()

 

#—————set constant——————————————-

a=0.46e-6

b=a*1e6

nx=14

ny=100

G=11

 

#—————-set FDTD————————————————-

 

fdtd.addfdtd(dimension=”3D”, x = 0,x_span=4*b*nx*1e-6, y = 0, y_min=-20*b/0.5*1e-6, y_max=ny*b*1e-6 , z = 0.0, z_span=220e-9)

fdtdObj= fdtd.getObjectById(“::model::FDTD”)

fdtdObj.simulation_time=3000e-15

fdtdObj.simulation_temperature=300

fdtdObj.background_material=”

 

 

[Guilin Sun]

 

Unfortunately we are not allowed to test script in this forum. Before running the FDTD, please check if the FDTD file is correct and proper. Once it is ok, you can use another python file to run it, in order to isolate the cause. Please try simple structure first.