Graphene-based PAM-4 modulator compatible with CMOS platform operating over DWDM C-Band

Abstract

The next generation of optical transport networks requires a small footprint, high channel capacity, low cost, and technology capabilities driven by CMOS technology. To achieve these requirements, we demonstrated from a calculus and simulation perspective a novel PAM-4 based on graphene, whose design and materials enable direct applications in telecommunications systems. The novelty is the four graphene-based capacitor-like segments integrated on a silicon platform, which consists of an optical digital-analog converter for the generation of symmetric multilevel PAM-4 coding transmission with a very compact layout. The ultra-high transmission capacity (136 Gbps) is enabled by optimizing a silicon waveguide and the technics to reduce the capacitances and an innovative technique based on the graphene's inductor that reduces the on-chip area (compared to its similar metal inductor) and improves the frequency response. Here, we demonstrate how the design overcomes the trade-off between the low switching voltage 1.4 V (CMOS-compatible drive voltage) while supporting very high bandwidths over the entire DWDM C-Band, without any additional reconfiguration.

Keywords

• Electro-optic modulators
• Integrated optics
• Optical interconnections
• Optical transmitters
• Silicon photonics
• Multilevel optical modulation