High-contrast, large optical bandwidth field-induced guide/antiguide modulator

We report an electric field induced-guide/antiguide optical intensity modulator which has a very wide optical bandwidth from 1 to 1.55 μm (ON/OFF ratio ≳ 13 dB from 1 to 1.55 μm for both TE and TM modes), which is the largest ever reported before for an intensity modulator. A TE mode ON/OFF ratio larger than 21 dB at 1.15 μm, and a propagation loss ∼1 dB at 1.3 μm has been measured. The electro-optic effects, along with carrier effects have been exploited to increase the refractive index under the guide and adjacent antiguide electrodes by applying reverse biases to them.