A plasmonic modulator based on a metal-insulator-metal waveguide with a barium titanate core

We design a plasmonic modulator which can be utilized as a compact active device in photonic integrated circuits. The active material, barium titanate (BaTiO3), is sandwiched between metal plates and changes its refractive index under applied voltage. Some degree of switching of ferroelectric domains from the in-plane to out-of-plane orientation provides the change of the refractive index, which can be exploited for effective light modulation. By numerical analysis we prove that the pi phase change can be achieved with a 12 ... 15 mu m length device having propagation losses 0.05 ... 0.2dB/mu m.