Key points are not available for this paper at this time.
Record-low loss of 0.149dB/km at 1550nm is realized by pure-silica-core fiber having optimally enlarged Aeff, which indicates record-high figure-of-merit for digital coherent system. Mass-productivity is verified with 7,000km long fabrication whose averaged loss of 0.154dB/km.
Hirano et al. (Tue,) studied this question.