New hollow-core optical fibre can speed up data transmission by 45 pc, researchers say

New Delhi, Sep 1 (PTI) Researchers have designed a new type of optical fibre, which guides light through air in its hollow core -- instead of the traditional solid glass -- and can therefore increase the speed of transmitting information by up to 45 per cent.

Described in the journal Nature Photonics, the design could also offer the lowest levels of information loss ever recorded for an optical fibre, allowing more data to be sent over larger distances before requiring boosting, researchers said.

The team from Microsoft Azure Fiber and the University of Southampton in the UK said the innovation potentially heralds "a new era in long-distance communications".

Typically, an optical fibre -- used extensively for telecommunications -- is cylindrical in shape and made of solid silica glass, which limits transmitting information without loss, despite decades of optimisation, they said.

Light energy absorbed by the material of the optical fibre is among the reasons for information loss.

As such, about half of the light sent through the fibre is lost after about 20 km, requiring a regular use of amplifiers that boost signals for transmitting light over a longer distance -- such as across continents.

However, the optical fibre that the researchers have designed features a hollow core of air, surrounded by a fine pattern of thin silica rings to guide the light.

Tests in lab experiments revealed that the fibre caused an information loss of only 0.091 decibels per km at a wavelength at which light travels for common optical communications.

As a result, light signals of suitable wavelengths could travel around 50 per cent further before needing a boost, the authors said.

Losses between 0.2 decibels per km and 3.5 decibels per km length of a typical optical fibre, depending on the wavelength of light being transmitted, have been documented in previous studies.

A bigger hollow core, allowing for more air to travel, could potentially result in even lower losses in information, even as more research is needed to confirm this, the authors noted.

"Instead of a traditional solid glass core, this innovative optical fibre features a core of air surrounded by a meticulously engineered glass microstructure to guide light. This approach not only reduces attenuation and other signal degradation phenomena, but it also increases transmission speeds by 45 per cent," the authors wrote.

They added that the design "theoretically supports further loss reductions and operation at wavelengths where broader bandwidth amplifiers exist, potentially heralding a new era in long-distance communications as well as remote delivery of laser beams." PTI KRS RHL