Efficient 330-Gb/s PAM-8 modulation using silicon microring modulators

We propose and demonstrate a high-efficiency silicon microring modulator for next-generation optical transmitters operating at line rates above 300 Gb/s. The modulator supports high-order PAM-8 modulation up to 110 Gbaud (330 Gb/s), with a driving voltage of 1.8 V-pp. The small driving voltage and device capacitance yields a dynamic energy consumption of 3.1 fJ/bit. Using the modulator, we compare PAM-8 with ultrahigh baud rate PAM-4 of up to 130 Gbaud (260 Gb/s) and show PAM-8 is better suited for 300-Gb/s lane rate operation in bandwidth-constrained short-reach systems. (c) 2023 Optica Publishing Group

Automated summary

We propose a high-efficiency silicon microring modulator for next-generation optical transmitters operating at line rates above 300 Gb/s. The modulator supports high-order PAM-8 modulation up to 110 Gbaud (330 Gb/s) with a driving voltage of 1.8 V-pp. The dynamic energy consumption of the modulator is 3.1 fJ/bit, thanks to its small driving voltage and device capacitance. Comparing PAM-8 with ultrahigh baud rate PAM-4 of up to 130 Gbaud (260 Gb/s), we demonstrate that PAM-8 is better suited for 300-Gb/s lane rate operation in bandwidth-constrained short-reach systems.