The latest article on silicon-based graphene modulator titled "Linearity of a silicon-based graphene electro-absorption modulator" by the Center's Ph.D. students Ming Jin and Yuansheng Tao was recently published in Optics Letters. In the group's 2019 OE article (https://doi.org/10.1364/OE.27.009013), the high linearity properties of silicon-based graphene modulators are theoretically verified. In this study, as a continuation of the previous work, a wafer-oriented mass-production silicon-based graphene optoelectronic device processing process was developed based on the CMOS process. A gate-electrode-type silicon-based graphene electro-absorption modulator (Fig. 1) was prepared, and its high-speed modulation, linearity, and other characteristics were investigated.

Figure 1

Based on this modulator, the researchers demonstrated the high linearity characteristics of a silicon-based graphene electro-absorption modulator experimentally and transmitted PAM4 signals on the order of Gbps rate for the first time (Fig. 2).

Figure 2

Further theoretical analysis demonstrates that the linearity of the graphene-on-silicon modulator is not affected by commonly used schemes that optimize bandwidth and modulator efficiency (Fig. 3). This finding demonstrates the potential of silicon-based graphene modulators for future high-speed microwave communication applications.

Figure 3

The main collaborators of the above work include members of Prof. Hailin Peng's group at the School of Chemistry, Peking University, and Jianbo Yin, a researcher at the Beijing Graphene Research Institute. This project is supported by the National Natural Science Foundation of China, the National Key R&D Program, and the Key R&D Program of Beijing Science and Technology Commission.

Link to the paper:

https://doi.org/10.1364/OL.459876