Design of High-Performance Optical TE Modulator Based on Si/VO2/Si Structure

Phase transition in vanadium dioxide (VO2) from insulation to metallic phase, makes it an attractive candidate for the realization of electro-absorption modulators. In this paper, we investigate and design a high-performance modulator at the telecommunication wavelength of λ = 1.55 μm, based on a silicon rib waveguide incorporated with a nanostrip V02 layer. The modulator utilizes an asymmetric structure for enhancing the modulation depth and reaching the minimum insertion loss. We show that for transverse electric optical modes, the asymmetric structure shows better characteristics. The results show a high-modulation depth of about 6.54 dB/μm and the corresponding insertion loss of about 1.34 dB/μm.