Integrated electro-optic modulator on a lead zirconate titanate-silicon nitride heterogeneous platform

Integrated electro-optic (EO) modulators are the core components of the optoelectronic information technology, and lithium niobate is currently the most widely used crystalline thin film material; however, finite EO coefficients limit the modulation efficiency of the modulators. In this Letter, we present an integrated EO modulator using a microring resonator on the lead zirconate titanate (PZT) and silicon nitride (SiN) heterogeneous platform. The microwave attenuation is reduced by using low loss tangent and dielectric constant SiN as the electrode substrate, achieving an EO bandwidth of 33 GHz. Thanks to the high quality of the PZT film deposition and the substantial EO overlap of our structure, ultrahigh modulation efficiency with the half-wave voltage-length product of 0.7 V·cm is achieved. In addition, as a remarkable result, an 80-Gbps on-off keying signal is generated using the modulator.