100 GBaud DSP-Free PAM-4 Optical Signal Generation Using an InP-DHBT AMUX-Driver and a Thin-Film Lithium Niobate Modulator Assembly

• Main Authors: Hersent, R., Jorge, F., Blache, F., Duval, B., Goix, M., Mardoyan, H., Almonacil, S., Xu, M., Zhu, Y., Chen, L., Hu, Z., Renaudier, J., Riet, M., Konczykowska, A., Ardouin, B.
• Format: Conference Proceeding
• Language: English
• Subjects: 4-level pulse amplitude modulation (PAM-4); Analog-multiplexer; Bandwidth; high-speed analog integrated circuits; Indium Phosphide (InP) double heterojunction bipolar transistor (DHBT); Integrated optics; large-swing linear modulator driver; Lithium niobate; Mach-Zehnder modulator; Optical films; Optical modulation; Optical signal processing; Tb/s optical communications; thin film lithium niobate (TFLN); Transceivers
• ISSN: 2831-4999
• DOI: 10.1109/BCICTS54660.2023.10310947

In this article, we report on the generation of 100-GBd (200-Gb/s) 4-level pulse-amplitude modulation (PAM-4) optical signal, without any support of digital signal processing (DSP) nor off-line equalisation. This is achieved in using an uncooled indium phosphide (InP) analog-multiplexer (AMUX)-driver and a thin film lithium niobate (TFLN) Mach-Zehnder modulator (MZM) assembly, with a -3-dB electro-optical bandwidth in excess of 85 GHz. This result paves the way for low-power DSP-free beyond-1-Tb/s transceivers for next generation optical communication systems and 6G applications. We also present the design and characterisation of the AMUX-driver integrated circuit (IC). The InP-DHBT IC shows a 2-Vppd output swing at 100 GBd in PAM-4 while operating at a 100-GSa/s sampling-rate.