Ultra-broadband Mach-Zehnder hybrid electro-optic polymer/sol-gel silica waveguide modulators

摘要

We demonstrate ultra-broadband Mach-Zehnder (MZ) electro-optic polymer/sol-gel silica waveguide modulators. A bandwidth of an electrical transmission S₂₁ is measured at a modulation frequency of up to 50 GHz (upper limit of our electrical equipments), which extrapolates the 6 dB bandwidth of 130 GHz base on an experimentally obtained device parameters. The electrical transmission in dB scale is linearly dropped with respect to a modulating frequency with extremely small deviation dip of less than 0.5 dB. Large signal measurements at a transmission rate of 56 Gbit/s (upper limit of our electrical equipments) show clearly opened eye-diagram. The half-wave voltage and electrode length product is 4.15 Vcm (a single-driving) for an electrode distance of 13.3 μm, which corresponds to 2.08 Vcm for a dual-driving. An in-device electro-optic coefficient r₃₃ is 140 pm/V at a wavelength of 1.55 μm for the ultra-broadband MZ modulators.