Traveling wave Mach-Zehnder modulator

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To help us solve your issue as quickly as possible, please provide the following information:

1. What device are you trying to simulate? Include diagrams if available.

Traveling Wave Mach-Zehnder modulator explained in the link here:

2. What results are you trying to obtain? Be as specific as possible.

Variation of RF effective index as a function of doping. Group index calculation is explained in step 4 of the link.

3. Description of the problem or issue.

In step four, it is written " The values of the slab resistances and pn junction capacitance (at zero bias) are copied from step 2 and set from the script." However, I am not able to figure out which part of the script does it.
In this section,
#Set slab resistance and pn junction capacitance at zero bias

setnamed(‘n’,‘r’,6901.86); #Ohm for 1 um length in y direction


setnamed(‘junction’,‘c’,0.2098e-15); #F for 1 um length in y direction

I think resistance and capacitance are set but they are setup manually instead of exporting from step 2. Please let me know how to do it. I am new to Lumerical script so I might have missed something.
4. Lumerical product and software version.

Lumerical 2019b Mode and Charge.

5. Please attach your simulation files, including any logs.

Hello @awanish.pandey,

You are correct, the values for the resistance and capacitance are set manually in these lines. This is done because these values are from a CHARGE simulation, while step 4 uses a MODE simulation. Some more work would be required to get the results from CHARGE to MODE automatically.

One option would be to use the Python API to run the files from the example in the different solvers in sequence, and pass the resistance and capacitance results between the solvers in the Python script. However, unless you are planning on doing a large number of simulations with different parameters, it might be faster to simply manually copy the values into the script.

I hope this helps. Let me know if you have any questions.