Thin-Film Lead Zirconate Titanate Nanobeam Electro-Optic Modulator

Abstract

The integration of electro-optic (EO) films on an insulator/silicon (Si) substrate presents opportunities to enhance the performance of devices with novel electronic and photonic properties. Among these EO films, lead zirconate titanate (PZT) exhibits attractive optical properties and a particularly strong Pockels effect. Here, we demonstrate ultracompact EO modulators incorporating PZT thin films on the ubiquitous SiO₂/Si substrate based on the photonic crystal nanobeam resonator. With a moderate Q-factor in the designed distributed feedback resonator, the modulator exhibits a notable tuning efficiency of 21.2 pm under an applying voltage of 1 V and a broad modulation bandwidth of 37 GHz while maintaining a device length of only 50 μm. The device can support an ultrafast modulation of up to 80 Gbit/s and meanwhile features excellent reliability with a negligible power shift at a bias of 3 V even after 60 min. The ultracompact and high-speed PZT modulators could pave the way toward realizing dense photonic integrated circuits for broad applications in data communication, microwave photonics, and quantum photonics.