High electro-optic coefficient lead zirconate titanate films toward low-power and compact modulators

Developing strong electro-optic (EO) effect materials and devices is vital for high-speed optical communications and integrated photonics. In this work, we explored a chemical solution deposition technique to grow pure perovskite lead zirconate titanate (PZT) films on sapphire substrates. The grown PZT films demonstrated a preferential orientation and a broadband optical transmission window ranging from 600 to 2500 nm. Based on the high-quality film, we subsequently designed and fabricated a PZT Mach-Zehnder interference waveguide EO modulator. The measured half-wave voltage V_π is 3.6 V at the wavelength of 1550 nm, corresponding to an in-device EO coefficient as high as ∼133 pm/V. The response of the PZT modulator from 6 to 12 GHz has been measured. We foresee that our work may pave the way towards power-efficient, ultra-compact integrated devices, including modulators, switches and sensors.