9 Tb/s Transmission using 29 mW Optical Pump Power per EDFA with 1.24 Tb/s/W Power Efficiency over 15, 050 km. - Jin-Xing Cai; Matthew V. Mazurczyk; G. Vedala; Yue Hu; Oleg V. Sinkin; Maxim A. Bolshtyansky; Dmitri G. Foursa; Alexei N. Pilipetskii (OFC, 2021)