Researchers manufacture record length of high-performance photonic bandgap fibre

Researchers at the University of Southampton’s Zepler Institute have successfully manufactured a record 11km of hollow core photonic bandgap fibre with low loss and a broad transmission bandwidth – a type of fibre that until now had only been made in lengths of hundreds of metres.

The fibre, which supports >200nm bandwidth with a longitudinally uniform loss of approximately 5dB/km at 1560nm, has a 19 cell core and 5 cladding ring structure and was fabricated using a conventional two-stage stack-and-draw technique.

“Hollow core photonic bandgap fibre has only had niche applications up until now because it was thought that it could not be manufactured in lengths suitable for telecoms applications,” said Dr Marco Petrovich a senior member of the Zepler Institute team developing hollow core fibre technology with funding from both the UK Engineering and Physical Sciences Research Council and European Union FP7 programme. “Not only have we successfully made a photonic bandgap fibre in a suitable length, we have also engineered it to have the right properties for telecoms applications.”

Petrovich and his colleagues have demonstrated that the fibre has error-free, low-latency, direct-detection 10Gbit/s transmission across the entire C-Band.

Manufacturing long lengths of photonic band gap fibre is notoriously difficult because unlike conventional fibres whose properties depend on the materials used to make them, the properties of photonic bandgap fibres depend on their structure. The nodes and struts that give photonic bandgap fibre its properties are usually on a sub-micron scale with many even just a few nanometres in size. “Any small change in these structures can change the properties along the fibre,” said Petrovich. “We have shown that our fibre’s properties are consistent along its entire length.”

The breakthrough was made possible due to an improved understanding of fibre properties deriving from various new numerical and experimental fabrication and characterisation tools recently developed by the team of researchers.

“We demonstrated data transmission at 10Gb/s along a 11km span using direct detection, showing only minor penalties and achieving an estimated >15μs latency reduction relative to standard fibre,” said Petrovich. “Our numerical models of the fibre drawing process give us confidence that much longer fibre yields are feasible through further scaling of the process, and that much lower loss fibres should ultimately be possible.”

Details of the research can be found in the following publication: Y. Chen et al., Demonstration of an 11km Hollow Core Photonic Bandgap Fiber for Broadband Low-latency Data Transmission, OFC Th5A.1 (2015)

Notes to editors:

• Photonic band-gap fibre is a type of microstructured fibre. Microstructured fibres are a revolutionary new type, which can be made entirely from one kind of glass, as opposed to the solid optical fibres used today which rely on the addition of chemical elements (dopants) to enhance light guidance through glass. In microstructured fibres, the cladding region is peppered with many small air holes that run the entire fibre length. In photonic band-gap fibres light guidance in the hollow core can be achieved via photonic band-gap effects.
• The Zepler Institute is the University of Southampton’s multidisciplinary centre for photonics, electronics and quantum technologies. It is the largest of its kind in the UK and was launched in 2013 by Vint Cerf, Vice President and Chief Internet Evangelist for Google. The Institute Director is Professor Sir David Payne, a world-class technology pioneer; the vast transmission capacity of today’s internet results directly from the erbium-doped fibre amplifier (EDFA) invented by Sir David and his team in the 1980s. www.zeplerinstitute.com
• The fibres are fabricated in Zepler Institute’s £120m Cleanroom Complex with the widest range of optical fibre fabrication technology in the world. www.zeplerinstitute.com/facilities
• The Zepler Institute includes within its community, researchers from the Optoelectronics Research Centre (ORC), University of Southampton. The ORC is one of the world’s largest university-based research groups devoted to optoelectronics. Its long track record in optical fibre, lasers, waveguides, devices and optoelectronic materials has fostered innovation, enterprise, and multi-disciplinary activities. www.orc.soton.ac.uk
• The hollow core fibre technology has been developed as part of research carried out in the Centre for Innovative Manufacturing in Photonics (CIMP), University of Southampton and the Transforming the Internet Infrastructure – The Photonics Hyperhighway research programme, both funded by the Engineering and Physical Sciences Research Council (EPSRC), and part of the MODE-GAP project, funded under the European Union 7th Framework Programme.
• The CIMP has been set up with world-class facilities to research into advanced manufacturing using photonic materials, fibres and components. It seeks to enable UK firms to extend their product portfolios and introduce innovative yet cost-competitive manufacturing processes. www.cimp.soton.ac.uk
• The Transforming the Internet Infrastructure – The Photonics Hyperhighway research programme combines the world-leading expertise of the University of Southampton, Optoelectronics Research Centre and the High Performance Network Group, University of Essex, to pioneer the internet infrastructure of the future along with industry partners: BBC Research and Development, Fianium and Oclaro. http://phh.orc.soton.ac.uk
• MODE-GAP is a collaborative R&D project which aims to develop the disruptive technology and concepts needed to enhance our communications infrastructure 100-fold to avert network gridlock and reduce energy consumption. www.modegap.eu
• Members of the Zepler Institute team will be at Laser World of Photonics, Munich, Germany, June 22-25 2015 (ORC Stand B2 139).