Optical modulator using silicon photonic crystals/nano-montmorillonite

In this paper, a novel compact optical modulator based on silicon photonic crystals /nano-montmorillonite is proposed. The two-dimensional silicon photonic crystal with triangular lattice and a line defect waveguide formed by a missing row of air holes in the Γ -K direction. The lattice constant is a, and the diameter of the holes is d=0.4a. The holes are filled with the nano-montmorillonite electrorheological fluid, which is made of nanometer sized nano-montmorillonite. The light modulation mechanism of the novel modulator is based on a dynamic shift of the photonic band gap. We have investigated its light modulation performance by using the finite-difference time-domain method. The numerical results show that an excellent optical modulator at a wavelength of 1550nm is achieved. The novel modulator has a high extinction ratio (close to -40dB) and small size (around 10μm). It is very suitable for forthcoming photonic integrated circuits.