Net 6.4 and 7.6 Tbps BiDi Transmission Over 10 km Hollow-Core Fiber for AI Data Center Based on $8 lambda-225$ GBaud PAM4/6. - Yao Zhang; Haiyun Xin; Jin Tang; Qiang Guo; Haofan Yang 002; Maxim Kuschnerov; Huixiao Ma (ECOC, 2025)