Learning Forum

[Evangelia Chatzianagnostou]

Hello,

I am writing about a problem I am facing with a simulation with the EME solver.

Specifically, I am trying to simulate a structure with 2 ports and 3 cells.

Firstly, I calculate and select the modes I want in the two ports and I run the simulation.

In the ports, I solve for 10 modes and I select the 2nd mode (it is the fundamental TM of a photonic waveguide).

Additionally,  I have selected custom settings for the 3 cell groups in order to be compatible with the port settings (e.g. search near n value). After defining the required settings (from 'Custom setting for cell group 1') I calculate modes and the resulted modes are the same with the ones calculated in the port, as expected.

However, after running the simulation (Analysis mode), the modes of cell 1 (Cell 1--> Visualize-->mode fields) are different from the ones calculated previously in the Port 1 and Cell 1 (some are same but with different order).

I am also attaching a plot of the neff vs mode number for the modes calcylated in Port 1 and the modes I take from Cell 1 after running the simulation from the Cell 1--> Visualize-->mode fields.

Can you be of any help?

 

[Guilin Sun]

It seems the mode sequence is changed. Please install the latest version and see if this issue still exists. Please also check if this is random. If after upgrading it still has the same issue, please let me know your computer OS version.

[Evangelia Chatzianagnostou]

Hello again,

 

I opened and run the file with the latest version but the problem still exists. The order of modes is the same as previous.

The OS is Ubuntu 20.04

 

(PS. I kept also the previous Lumerical version)

[Guilin Sun]

 

It seems the software has issue for this OS. could you please send us an email (suppor address) with your file attached, and indicate this post? I will need sometime to dig this more.