Lowering The Bit‐Energy of Electro‐Optic Modulators Via Polarization‐Phase Modulation in Thin‐Film BaTiO3 Ferroelectric Crystal Waveguide

Abstract

AbstractThe electro‐optic (EO) modulator is a crucial device for achieving high‐speed optical communication and optical interconnection by loading the high‐frequency electrical signals onto the optical carrier. To date, modern communication technique demands for a low energy consumption for green data center establishment. In this work, a thin‐film BaTiO3 crystal waveguide Mach–Zehnder interferometer (MZI) type EO intensity modulator is experimentally implemented and its dynamic‐polarization interference process involving a phase‐polarization modulation (PPM) scheme other than conventional optical phase modulation (OPM) is carefully analyzed. Its findings show that the PPM scheme can efficiently reduce the half‐wave voltage () and the equivalent half‐wave voltage () of the modulator. Then, a new theory of deriving the bit energy (BE) from is put forward, which has proven that the BE value under PPM is lower than the OPM counterpart. The EO modulator prototype featuring a length of 1.4 mm, = 3.0 V and BE = 1.2 pJ/bit match well with the numerical calculations, thus validating the feasibility to achieve a BE<0.2 pJ/bit for an EO modulator through optimization of the electrode gap and state‐of‐the‐art fabrication techniques in the near future.