Moduli Stabilization in Chiral Type IIB Orientifold Models with Fluxes

TL;DR

This paper explores stabilizing moduli in Type IIB string models using fluxes and magnetic fluxes on D-branes, achieving partial stabilization and chiral fermions in a simple orbifold example.

Contribution

It introduces a method to stabilize both complex structure and Kaehler moduli using fluxes and magnetic fluxes on D-branes in orientifold models.

Findings

Fluxes stabilize complex structure moduli and dilaton.

Magnetic fluxes on D-branes stabilize some Kaehler moduli.

Chiral fermions emerge from magnetic fluxes in the toy model.

Abstract

We consider Type IIB orientifold models on Calabi-Yau spaces with three-form G-flux turned on. These fluxes freeze some of the complex structure moduli and the complex dilaton via an F-term scalar potential. By introducing pairs of D9-anti-D9 branes with abelian magnetic fluxes it is possible to freeze also some of the Kaehler moduli via a D-term potential. Moreover, such magnetic fluxes in general lead to chiral fermions, which make them interesting for string model-building. These issues are demonstrated in a simple toy model based on a Z_2 x Z_2' orbifold.