Type IIB Flux Vacua at Large Complex Structure

We study models of stabilization near large complex structure in type IIB O3/O7 flux compactifications. We consider a special family of examples with a single nonvanishing Yukawa coupling in the large complex structure limit, which allows us to study all possible stable vacua of the tree-level no-scale potential very explicitly. We find that, by tuning fluxes, both supersymmetric and nonsupersymmetric vacua can be realized at almost any point in the large complex structure moduli space of one-, two-, and three-parameter models. We also consider the effects of stringy corrections on tree-level vacua. We argue quite generally that, in certain regimes, both supersymmetric and nonsupersymmetric tree-level vacua could serve as consistent, controllable foundations for full stabilization beyond tree level (including Kahler moduli), leading to either AdS or dS cosmological constants. We show how to achieve these regimes in our models. Finally, we discuss some implications of minimizing at tree level the no-scale form of the scalar potential, versus other potentials used in statistical studies.