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arXiv · 2608.14901

Quasi-Single-Mode Transmission over Ultra-Low Loss Few-Mode Fibre for Data Centre Interconnects

Fabio A. Barbosa·Rostislav R. Khrapko·Ming-Jun Li·Filipe M. Ferreira
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Abstract

A novel ultra-low-loss few-mode fibre is experimentally investigated for quasi-single-mode transmission over data centre interconnect distances. Multipath interference is characterised across the C-band matching a modified Gaussian noise model to experimental results obtained with conventional training-sequence-based digital signal processing, enabling inservice assessment without traffic disruption. This model shows strong agreement with power-fluctuation measurements performed on a dedicated unmodulated-laser setup. The impact of equaliser length and digital backpropagation on system performance is also analysed. Compared with standard ultralow-loss single-mode fibres, transmission experiments reveal only minor signal-to-noise ratio degradation for up to 42-Gbaud DP-256-QAM over a 24-km span. These findings highlight the potential of ultra-low-loss few-mode fibre for scalable, highcapacity data centre interconnect applications while offering potential for future space-division multiplexing upgrades.

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Fabio A. Barbosa, Rostislav R. Khrapko, Ming-Jun Li, Filipe M. Ferreira. 2026-08-14. Quasi-Single-Mode Transmission over Ultra-Low Loss Few-Mode Fibre for Data Centre Interconnects. https://arxiv.org/abs/2608.14901

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