Macquarie Uni coupler enables super-fast fibre, a potential antidote to 'capacity crunch'

​A coupler developed by researchers at Macquarie University Photonics Research Centre has enabled transmission of more than a petabit of data per second down an optical fibre as fine as a human hair.

George Nott Nov 16th 2018

A coupler developed by researchers at Macquarie University Photonics Research Centre has enabled transmission of more than a petabit of data per second down an optical fibre as fine as a human hair.

The “world-first”, new type of fibre allows for data speeds 12 million times quicker than the fastest NBN connection, the researchers claimed today.

The fibre, jointly developed by Hokkaido University and Fujikura Ltd, is slightly narrower than standard optical fibres but can transmit 12 times as much data per second.

Standard fibre typically has one optical path (core) which supports one kind of optical signal (mode). Despite being about the same diameter, the new fibre has four cores and three modes, giving it significantly more capacity.

“The world’s insatiable demand for data means that we are approaching a ‘capacity crunch’ and need to find new ways to transport ever-larger volumes,” said Macquarie Uni’s Dr Simon Gross.

Work to date towards boosting the capacity of optical fibres is focused on ‘space multiplexing technology’ – either with multi-core fibre which allows for many cores in one fibre, or multi-mode fibre to support many modes in one core.

However, until recently obtaining more than 50 communication pathways had proven difficult without increasing the diameter of the glass in the fibre.

The diameter of the glass is important, as the bigger it gets the more easily broken and less reliable the fibre becomes.

The new fibre – proven with a transmission system developed by the National Institute of Information and Communications Technology Japan (NICT) – has a “narrower diameter meaning it is less prone to damage and can easily be cabled and connected using existing equipment, resulting in significant cost-savings over other types of fibres” Gross said.

The researchers said the new fibre type had applications in transmitting data between data centres, across metropolitan networks, and down undersea communications cables, “with the ability to smoothly accommodate traffic for big data and 5G services”.

“This technology promises a solution to the bottleneck created by existing optical fibres. For the first time, we have created a realistic and useable-sized fibre which is resilient and can transport huge amounts of data,” Gross said.

“It also represents a big cost saving over installing the 12 standard optical fibres you would need to transport the same volume of data,” he added.

Crunch time

There has been a spate of cable laying in Australia’s waters in recent months. The 4850-kilometre INDIGO Central submarine cable landed at Coogee Beach last month, linking Sydney to Perth. The Perth to Singapore, 4600-kilometre section – INDIGO West – landed in Australia in September. Vocus finished laying its Australia Singapore Cable in July.

Nevertheless, a “capacity crunch” has been feared for some time. In 2010, David Richardson of the University of Southampton, wrote in Science on the need for innovation in “the actual light pipes”.

“Without radical innovation in our physical network infrastructure – that is, improvements in the key physical properties of transmission fibres and the optical amplifiers that we rely on to transmit data over long distances – we face what has been widely referred to as a ‘capacity crunch’ that could severely constrain future Internet growth, as well as having social and political ramifications,” Richardson wrote.

Increased demand for on-demand streaming and data heavy tools means we are “fast approaching the limits of existing communications networks,” Gross said, adding that the new fibre could prove to be a solution.