Graphene-Based Polarization-Independent Mid-Infrared Electro-Absorption Modulator Integrated in a Chalcogenide Glass Waveguide

Abstract

A polarization-insensitive graphene-based mid-infrared optical modulator is presented that comprised SiO2/ Ge23Sb7S70, in which two graphene layers are embedded with a semiellipse layout to support transverse magnetic (TM) and transverse electric (TE) polarizing modes with identical absorption. The key performance index for the polarization independent modulator is polarization-sensitivity loss (PSL). The waveguide of our device just supports basic TE and TM modes, and the PSL between two modes is of < 0.24 dB. The model can offer extinction ratio (ER) more than 16 dB and insertion loss less than 1 dB. The operation spectrum ranges from 2 to 2.4 μm with optical bandwidth of 400 nm. The 3 dB modulation bandwidth is as high as 136 GHz based on theoretical calculation.

Polarization-insensitive reverse-ridge AlGaAs waveguide for the mid-infrared supercontinuum generation

“…Chen et al proposed a polarization-insensitive graphene modulator, which was polarization-independent for the TE and TM modes [33]. Zhou et al reported a polarization-insensitive graphene-based optical modulator integrated in a chalcogenide glass waveguide [34], where the absorption coefficient variation was almost identical in the wavelength range of 2-2.4 μm for the TE and TM modes. However, there is still no report on the polarization-insensitive waveguide for the SC generation.…”