A 56-Gb/s, 6.3-pJ/bit PAM-4 DFB Laser Driver Incorporating Asymmetric Equalization and Integrated CDR in 28 nm CMOS. - Yang Min; Nan Qi; Yihan Chen; Yi Zhang; Minye Zhu; Guike Li; Yonghui Lin; Huiyao Peng; Mo Guang; Kaiwen Long; Zhao Zhang 004; Jian Liu 021; et al. (IEEE Trans. Very Large Scale Integr. Syst., 2025)