Abstract

For decades, the Pockels effect in lithium niobate (r ~ 30 pm/V) has been exploited to modulate and switch light in devices for telecommunication applications [1]. Since the Pockels effect is a pure electric field effect and is present even at short time scales of few ps, it enables power-efficient high speed devices. However, the emerging field of silicon photonics with highly integrated photonic circuits cannot benefit from this mature technology due to the vanishing Pockels effect of silicon and the difficulty of integrating lithium niobate onto silicon. With the recent success of growing high-quality, epitaxial barium titanate (BTO) thin films with strong Pockels coefficients of r_Eff ~ 148 pm/V directly on silicon [2], a new concept is now available for engineering functional silicon photonics networks [3,4]. In this work we elaborate a method of how to integrate nonlinear BTO thin films into silicon photonic structures. We also validate our design by fabricating and characterizing passive and active silicon photonic devices.

© 2015 IEEE