EME directional coupler example file


#1

Hello,

I am trying to simulate the power distribution as function of length in an asymmetric coupler. I found one example file, but I do not know how to obtain the image from the field monitor as shown here:
https://kb.lumerical.com/en/pic_passive_waveguide_couplers_evanescent.html

I downloaded the script. By default EME was active. I pressed start and after the simulation I only found the mode porfiles under port_1, port_2 and cell_1. But I cannot find anything under monitor.
And then my follow up question would be how to obtain a graph of the cross coupling as function of coupler length.

Edit:
I found the issue with the monitor. After running the EME simulations the EME analysis window pops up. At the bottom of this window is a check box for ‘update monitors’. If this is checked and after pressing ‘eme propagate’, then after a delay the monitors will have data inside of them. During this delay there is no indication of what is happening or where the result will be. After this delay there is still no indication it did anything and when right clicking the monitor there is data inside.

For my follow up question. What I did in my own script was apply an offset to the waveguides at both sides (port 1 and port 2) as shown for 1 port in the example. This issue I had was that the output graph still only showed some noise. This was due to EME only finding modes in the substrate. With the function seteigensolver behind select(“EME::Ports::port_1”); I managed to solve this problem for the modes at port 1 and port 2, but not inside the EME cells.

Which is where I am stuck, because as far as I can find there is no function to set the index search range inside EME cells by script.
https://ix.lumerical.com/ideas/MODE-I-3


#2

Hi @l.wevers

From the linked direct, you can download the simulation file and script. If you run the script, you will obtain intensity as a function of wavelength:

image

Was this the plot that you were referring to?

And thanks for updating us regarding your inquiry. The monitors will be populated by data after eme propagate button is pressed. There will be a red box over the monitor. For more details on how the monitors are populated by data, please see the “plot results” section in the link below:
https://kb.lumerical.com/en/index.html?pic_passive_getting_started_ring_resonator_fdtd_instructions.html

Unfortunately, we do not have that control, however, you can manually modify it from EME setup tab:


#3

This topic was automatically closed 3 days after the last reply. New replies are no longer allowed.