PRESS RELEASE: ZTE Corporation has partnered with YOFC, a global leading provider of optical fibre preforms, optical fibres, optical fibre cables and integrated solutions, to demonstrate the industry’s first real-time transport of a single-wavelength 1.2Tb/s with 3W (34.8dBm) launch power over a 20km hollow-core fiber. This achievement successfully verifies the ultra-low non-linear Kerr effect and ultra-low Stimulated Raman Scattering (SRS) effect of the hollow-core fiber system, marking a key milestone towards achieving longer-distance and larger-capacity transport over hollow-core fiber in the future.
With continuous breakthroughs in the manufacturing process, the attenuation coefficient of hollow-core fiber is steadily decreasing. This, combined with ultra-low latency and ultra-low non-linearity, is expected to revolutionize fiber communication systems. Using air as the transport medium, hollow-core fiber achieves a 47% higher optical signal transport speed compared to silica fiber, significantly reducing information transport latency. This improvement is particularly beneficial for latency-sensitive applications such as high-frequency trading, Data Center Interconnection (DCI), and AI large-model processing.
Additionally, due to the ultra-low energy ratio of optical signals in the glass, hollow-core fiber reduces the non-linear coefficient by 3-4 orders of magnitude compared to silica fiber. This reduction allows high-order modulation to be transmitted in the hollow-core fiber at high launch power, thereby maximizing spectral efficiency and enabling long-haul (LH) transport of high-order modulation to greatly increase system capacity.
To fully verify the ultra-low Kerr non-linearity of the hollow-core fiber, ZTE employs an Erbium-ytterbium co-doped Optical Fiber Amplifier (EYDFA) with saturated output power of up to 3W, along with a single-wavelength 1.2Tb/s PS-64QAM coherent optical module, to connect the 20km (currently the longest in China) hollow-core fiber from YOFC. The Kerr non-linear penalty is tested with different launch powers. The results show that when the launch power of a single-wavelength 1.2Tb/s signal is as high as 3W, no significant non-linear penalty is observed in the hollow-core fiber system. This indicates that the hollow-core fiber system has great potential for long-haul transport of high-speed and high-order modulation.
Additionally, the Stimulated Raman Scattering (SRS) effect is a key factor that restricts the transmission distance with ultra-wide bandwidth in silica fiber. In this verification, after an ultra-broadband S+C+L 19THz dummy light is injected into a 20km hollow-core fiber, the measured SRS loss spectrum shows that the extended bandwidth does not cause a significant power transfer effect. This verifies the ultra-low Raman transfer feature of hollow-core fiber, opening up a new path for the evolution of optical networks towards ultra-large capacity.
To date, ZTE has served more than 100 countries and regions with its optical network products, which are widely recognized by industry experts both domestically and internationally.
Moving forward, ZTE is committed to collaborating with global partners to further advance the standardization and commercialization of hollow-core fiber systems. Together, they aim to build an intelligent digital world characterized by ultra-broadband optical paths, paving the way for a sustainable future of technological advancement.