Recent Progress and Emerging Trends in Specialty Optical Fibers: Design, Fabrication and Applications

Dear Colleagues,

Specialty optical fibers (SOFs) are usually created via the use of different materials and/or the incorporation of unique waveguide designs, compared to the conventional optical fibers. SOFs refer to optical fibers that are designed and manufactured to possess unique properties and functionalities for specific applications. As such, SOFs are often not particularly cost effective and easy to scale, since by design they are dedicated to solving certain challenges that cannot be addressed by conventional fibers. Nevertheless, SOFs play a crucial role in advancing many vital applications in areas such as optical communication, directed-energy application, advanced fiber optic sensing, high-precision metrology and spectroscopy, industrial welding and machining, etc.

For example, in the late 1990s, engineering the dispersion of fibers enabled dispersion-compensated fiber designs that could mitigate the effect of dispersion in conventional fibers to enhance the performance and reliability of fiber-optic transmission, such as increasing the data rate and transmission distance. In the past decade or so, specialty micro-structured fibers have led to significant improvements in high-power fiber lasers via the enhancement of the output mode quality and the lowering of nonlinearity at high power levels, which are achieved using specialty rare-earth-doped fibers for lasers and amplifiers. Very recently, a new generation of hollow-core fiber designs, based on photonic bandgap or anti-resonance effects, has revolutionized the lowest achievable transmission loss in optical communication. As of March 2024, the lowest reported loss in an anti-resonant hollow-core fiber at 1550 nm is 0.11dB/km. Another very promising trend is the application of SOFs, e.g., multi-core fibers, in revolutionizing data center architectures to boost the latest developments in machine learning and artificial intelligence. Quantum communication and computing platforms based on the photonic architecture are another area that could be boosted by specialty fibers. Lastly, it is reported that the market size of the Specialty Optical Fibers market is expected to reach USD 8 billion (approximately USD 25 per person in the US) by 2025, driven by the increasing adoption of fiber optic technology across various industries.

This Special Issue aims to present recent applications and original state-of-the-art research articles related to novel specialty optical fibers, including the design, manufacture, and application of specialty optical fibers. Both original research papers and review papers that focus on the design, development, and applications of novel specialty optical fibers are welcome. Researchers are invited to submit their contributions on theoretical/numerical modeling, the development of the fabrication process, fiber optic devices and components, and experimental characterization and measurements. Topics include, but are not limited to, the following:

• Novel fiber design and theory
• Fiber fabrication process development and modeling
• Novel dopants and glass compositions
• Novel fiber characterization and measurement
• Novel core fibers
• Micro-structured fibers
• Hollow-core fibers
• Anti-resonant fibers
• Photonic bandgap fibers
• Multi-core fibers
• Novel rare-earth-doped fiber lasers
• Single-frequency fiber lasers
• Multi-core and multimode fiber lasers
• Pulsed fiber lasers
• High-power fiber lasers and amplifiers
• Mid-infrared fiber lasers
• Fibers for sensors and spectroscopy
• Nonlinear effects in specialty fibers
• Optical communication devices
• Quantum photonic hardware
• Hollow-core fiber for high-power pulse delivery
• Hollow-core fiber for visible-light laser delivery
• Fiber optics devices with specialty fibers
• Fabrication of waveguides and components with specialty fibers
• Application of specialty fibers in optical communication

Dr. Turghun Matniyaz
Dr. Thomas Wade Hawkins
Dr. Sushmit Goyal
Guest Editors

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