Non-perturbative effects such as gaugino condensation on a stack of D7-branes are an essential ingredient in several celebrated moduli-stabilisation schemes in type IIB string theory. At the level of the four-dimensional effective theory, the non-perturbative effects induce a non-perturbative superpotential. In particular, new Yukawa interactions can be generated. Type IIB orbifold models contain the essential features to study these non-perturbative corrections to the superpotential in string compactifications. I will describe under which conditions new Yukawa couplings arise in these settings and generalise the results to more realistic string models. Most importantly, I will show that the flavour structure of the induced Yukawa couplings is not aligned with the tree-level flavour structure, thus introducing a new source of flavor violation.
view more