April 1, 2024 – Over the past year, driven by the id growth in AI computing power requirements and the continuous expansion of network capacity, there has been a pressing need for ultra-high bandwidth and ultra-low latency transmission capabilities. Hollow-core fiber, charactey its unique advantages of low latency, wide spectrum, low loss, and low nonlinearity, has garnered significant industry attention. Both domestic and international entities are accelerating their strategic lale advancing live network trials and commercialization efforts.

On March 26, the China International Optoelectronic Exposition (CIOE) collaborated with  to host the "2026 China Optical Communication High-Quality Development Forum – Hollow-Core Fiber Workshop." The event delved into the technical maturity and application scenario compatibility of hollower, analyzed the path to domestic breakthroughs across the entire chain from materials and fibers to devices and systems, and aimed to drive China's leapfrog development in the field of next-generation optical frastructure.

Hollow-core optical fibers hold broad prospects. Li Chunsheng, General Manager of Beijing University of Posts and Telecommunications Science Pao., Ltd. and Director of the BUPT Huafei Research Institute, stated that the performance of solid-core optical fibers is approaching the Shannon limit, with significant nonlinear effects that struggle to meet tgent demands of AI and computing networks for ultra-high speed, large capacity, and low latency. Hollow-core optical fibers can reduce network latency, possess ultra-wide transmission spectra, reduce nonlinea effects by 3-4 orders of magnitude, and lower transmission loss, making them an ideal choice for constructing future optical networks.

Tang Xiongyan, Deputy Director of China Unicom Research Institute and Chief Scientist, noted that given the characteristics of hollow-core optical fibers, they can significantly enhance AI training efficiency in ultra-low latency, ultra-large capacity AI computinetworks. In ultra-low latency financial industry applications, every millisecond and microsecond counts. Furthermore, hollow-core optical fibers can provide a stable, low-loss transmission channel for quantum key dribution. As 6G requires ultra-low latency, ultra-large bandwidth, and ultra-massive connectivity, hollow-core optical fibers have the potential to become a key transmission medium

Wang Dong, Technical Manager and Principal Researcher at the China Mobile Research Institute, further highlighted the application of hollow-core optical fibers in submarine cable systems spanning thousands to tens of thousands of kilometrs. However, submarine cable systems are also space-constrained environments, and the current dimensions of hollow-core optical fibers are not yet compatible with existing submarine cable configurations, requiring further improvement and optiation.

Feng Lipeng, Senior Engineer at the China Telecom Research Institute, indicated that if the cost of hollow-core optical fibers is sufficiently low, their ultra-low loss characteristics could enable hiptical power input in PON networks, significantly increasing the splitting ratio. Additionally, in 5G/6G fronthaul, hollow-core optical fibers can simultaneously transmit signalsy, achieving co-transmission of information and power.

It is understood that through the joint efforts of the industry, hollow-core fiber technology has made continuous progress, achieving rapid advancements in attenuationinterference (IMI), reduction of gas absorption peak intensity, and expansion of low-loss bandwidth. Currently, the attenuation coefficient has reached 0.04 dB/kminterference is maintained at -65 dB/km, and the drawing length of a single preform exceeds 91.2 kilometers. Furthermore, the cost of hollow-coas decreased by an order of magnitude, and production yield has improved by over tenfold.

However, hollow-core fiber faces challenges in WDM systems due to absorption peaks caused by imurity gases. Additionally, regarding industrialization, current validation spans less than 10 years, whereas deployment in live networks typically requires a service life of 20-25 years. onsequently, further research is needed on lifespan issues, as there is currently no long-term experimental verification or reliable lifespan model. More critically, the commercialization and widespread use of holloiber require the resolution of operation and maintenance issues.

The industrial chain ecosystem is becoming increasingly mature.

Li Chunsheng from Beijing University of Posts and Telecommunications stated that opportunities and challeges coexist. Hollow-core fiber has demonstrated promising application prospects, and despite numerous challenges, the industrial chain will overcome them one by one. On one hand, core technologies need to bekled; on the other hand, the industrial ecosystem must be built, unified standards jointly established, and application scenarios explored.

Chen Yong, Chief Engineer of OTN Product Planning at ZTE , introduced that as a global leading provider of optical network solutions, ZTE initiated research and development of hollow-core fiber optical network systems as early as 2022.y accurately measured the ultra-low nonlinearity index of hollow-core fiber for the first time, laying a solid practical foundation for the subsequent application of high-power and high-order modulation technologi hollow-core fiber systems. In 2024, ZTE was the first in the industry to identify multiple gas absorption challenges, a key discovery that provided significant support for advancing thrcialization of hollow-core fiber.

Meanwhile, relying on the HI-OTN intelligent optical network architecture, ZTE continues to deepen its research and development in hollow-core fiber system integration and intelligent technology. In December 2024, assisting industry partners such as China Mobile, it achieved a 377.6Tb/s bidirectional transmission over a single fiber using the S C L ultra-wide spectrum in the laboratory, setting a new high for technical verification; in June 2025, it again assisted China Mobile in achieving a 10,714-kilometer ultra-long-distance transmission of a 1T optical signal based on hollow-core fiber, breaking the world record.

Yu Hongkang, Technical Support Manager at VIAVI, introduced that compared to traditional solid-core fibers, hollow-core fibers offer superior performance but also bring new challenges to testing. For example, connection testing between traditional solid-core fibers and hollow-core fibers; high splicing loss in hollow-core fibers makes it difficult to define attenuation values; the new structure brings the influence of bending and stress; multiple wavelength transmission windows make testing more complex, etc. VIAVI is the first test vendor in the industry to launch a long-distance bidirectional test and certification solution for hollow-core fibers. Regarding OTDR testing, Yu Hongkang proposed five suggestions, providing the industry with a standard process guide for hollow-core fiber testing.

Sun Wei, Director of R&D and Senior Engineer at Jiangsu Hengtong Fiber Optic Technology Co., Ltd., introduced that Hengtong has achieved comprehensive optimization of restricted loss, surface scattering loss, and micro-bend loss in loss control, with theoretical attenuation as low as 0.02dB/km, completely breaking through the quartz limit of solid-core fibers. As of early 2026, Hengtong has laid out nearly twenty patents in the field of hollow-core fibers, covering core processes such as preform assembly, drawing pressurization, sealing and air pressure, and Raman amplification systems.

Pilot Projects Ongoing, Significant Results Achieved

It is understood that over the past year and a half, C three major operators have all launched pilot projects for hollow-core optical fibers in live networks. A total of six tenders have been issued, resulting in the deployment f over 1,500 core-kilometers.

Tang Xiongyan of China Unicom introduced that in October 2025, China Unicom completed its first live network pilot veron of hollow-core optical fiber in Nanjing, Jiangsu, with a total length of 4.2 kilometers. In the same month, it completed the commercial interconnectin of over 30 kilometers of hollow-core optical fiber from Shenzhen to the Smart Cloud Data Center in Tseung Kwan O and the Hong Kong Stock Exchange, as well as cross-border aications. In January 2026, China Unicom completed the verification of 7.5 kilometers of hollow-core optical fiber interconnection between core data centers in Hou, Zhejiang.

Wang Dong of China Mobile stated that China Mobile has been conducting continuous research and development on anti-resonant hollow-core optical fibers and transmission systems with partnrs since 2021. In 2025, China Mobile achieved a transmission distance record of 10,714 kilometers for a single wavelength of 1T in itratory using hollow-core optical fiber. Furthermore, it collaborated with partners such as Yangtze Optical Fiber and Cable, Huawei, and ZTE to launch China's first commercial hollow-core ol fiber line in Guangdong, providing services for cross-border financial businesses between Shenzhen and Hong Kong.

Feng Lipeng of China Telecom noted that China Telecom has deployed three live netw projects to explore the application potential of hollow-core optical fibers from multiple dimensions. The deployment in Hangzhou is primarily planned for verification of data center intra-city dual-active operations; the deploymin Guangzhou is used for interconnection between financial centers, with the current link achieving a latency of 0.93ms between Shenzhen and the Hong Kong Stock Exchange; the dloyment in Sichuan is planned for integration with quantum technology to verify the performance of quantum entanglement and Quantum Key Distribution (QKD) in hollow-core optical fiber

Ding Qi, an analyst at CITIC Securities, believes that hollow-core optical fibers will be primarily used for data center interconnection within tens of kilometers (with potential expansion to hundreds of kilomet can achieve large-scale replacement of G.654E fibers after cost reduction. The unit price in 2025 was approximately 400 million yuan, aare expected to decrease with scaled application. "We believe it may remain at a 5 billion yuan scale in 2026, and gradually reach a 10 bilyuan or even hundreds of billions of yuan scale by 2027/2028."

The "2026 China Optical Communication High-Quality Development Forum large-scale seminar series jointly organized by CIOE China International Optoelectronic Expo and C114 Communication Network. The next seminar is scheduled to go liveon April 23, with the theme "AI FTTR: Optical Intelligence Fusion, Renewing Access." It focuses on the fusion innovation of "AI FTTR," aiming to explorAI can drive the transformation of access networks from "connection pipelines" to "intelligent service enabling platforms," promoting the advancement of all-optical access to a higher level of intelligence, and prg more agile, reliable, and personalized network experiences for scenarios such as digital homes, smart parks, and industrial optical networks.