Compute the optical gain of a quantum well

[Dj1312]

TL;DR Summary

Search to compute gain of a quantum well. Stuck with maths or programming.

Summary: Search to compute gain of a quantum well. Stuck with maths or programming.

Hi everyone !

For a personal project, I search to compute the optical gain occurring on a semiconductor quantum well. I have based my calculations on a paper called
Investigation and comparison of optical gain spectra of (Al,In)GaN laser diodes emitting in the 375 nm to 470 nm spectral range. But unfortunately, I can not achieve the gain computation. I put also my Matlab code on https://github.com/Dj1312/qw_gain_simulation.

My questions are the following :
- did someone now a place/book where I can found a complete explanation of how to compute such a gain ? (maybe even a script !)
- if not, can someone quickly see if there is a mistake in the paper.
I try since a lot of days using different ressources, but I always find wrong results…

Thanks in advance for your help,
Dj1312.

 

[Cthugha]

That is hard to say because the code is pretty hard to read. How far have you verified that the individual steps work?
I suggest that you either convert all units to eV and equivalents or Joules and equivalents at some point in the beginning and then stick to it. Moving back and forth in every new equation and function is bound to lead to disaster. The first thing I noticed at a quick glance is that in the function fun_G_hom there is a sech, where you divide a difference in frequencies in Hz by a linewidth in electronvolts. This will obviously give incorrect results. There may be more similar errors, but it will be tiresome to find them the way the code is written right now.