# Homework Help: Internal quantum efficiency (IQE)

1. Nov 22, 2017

### whatisreality

1. The problem statement, all variables and given/known data
The IQE is defined as (photons emitted from active region $s^{-1}$) / electrons injected across the junction.
Derive an expression for this quantity, then find the injected electron concentration $n$ which maximises it.
2. Relevant equations

3. The attempt at a solution
We've been taught that radiative recombination is given by $\sim Bn^2$, SRH recombination by $\sim An$ and Auger by $\sim Cn^3$. So then is the expression for IQE just
$\eta = \frac{Bn^2}{An + Bn^2 + Cn^2}$
It doesn't seem like much of a derivation, so I'm concerned that this is wrong or that I've missed something that needs to also be considered. Thanks for any help!

2. Nov 27, 2017

### PF_Help_Bot

Thanks for the thread! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post? The more details the better.