Complex oxides, such as BaTiO3, offer the potential for extremely high electro-optic response and can be grown on silicon to realize compact modulators in photonic integrated circuits. This Thrust will explore the fundamental science of several emerging complex oxides, including the impact(s) of their morphology and domain characteristics on their resulting electro-optic response. Synergistically with Thrust I, we will explore the electro-optic response of digital alloys.