Multiplicity-free tensor products of irreducible modules over simple algebraic groups in positive characteristic

Let $k$ be an algebraically closed field of characteristic $p>0$. In this master thesis, we classify multiplicity-free tensor products of simple modules for the groups $SL_2(k)$ and $SL_3(k)$. We also provide a classification for $SL_n(k)$ when $p=2$ and give partial results in the case of $Sp_4(k)$.