Learning Forum

[mhu]

Hello,

I am designing a device where it has multiple photodiodes. From lumerical photodiodes example I can see that I can define source intensity/power at hole-pair generation tab (CW_generation) in FDTD simulation. While simulating for single photodiode if I define at the hole-power generation tab that the source power is 1 watt then in charge simulation I will get the I-V curve and responsivity for 1 watt.

But In my device multiple photodiodes are getting input power from a common mode source through a coupler. Assuming first photodiode is getting 30% input power from the mode source 2nd one is 20% and so on. So, in this case how can I define source power/intensity at the electron-hole pair generation tab for each photodiode?

My Idea : I asssumed that the mode source has 1 watt power. I set a power monitor at each photodiode's input to measure what percentage of mode is coming to each photodiode. Based on this measurement, I will devide the 1 watt power to all the photodiodes. Suppose 1st photodiode is getting 30% of mode so it will get 0.3 watt and 2nd photodiode is getting 20% of mode so it will get 0.2 watt source input. Then I will set those measured powers at the generation tab for each photodiodes.

 

Thank you!

[Guilin Sun]

You are right that each channel can get the percentage it receives.

However, you may know that, the online example is normalized to 1W, and it is only for easy use for CHARGE.  You can change the "scale factor" to set the specified total power for each channel. For exmaple, channel one has 30% total power. If the total injection for this device is 1mW, you can set the scale factor of the eh import source for this channel one to be 0.3*1e-3.

Please try. 

[mhu]

Okay! I will try it.

Thank you for your answer and suggestion.