On the minimal extension and structure of weakly group-theoretical braided fusion categories

We show any slightly degenerate weakly group-theoretical fusion category admits a minimal extension. Let d be a positive square-free integer, given a weakly group-theoretical nondegenerate fusion category C, assume that FPdim(C) = nd and (n, d) = 1. If (FPdim(X), d) = 1 for all simple objects X of C, then we show that C contains a non-degenerate fusion subcategory C(Zd, q). In particular, we obtain that integral fusion categories of FP-dimensions pd such that C ⊆ sVec are nilpotent and group-theoretical, where p is a prime and (p, d) = 1.