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glass fiber @ 0.997 c

Jacob Aron Nothing is a bro, I can't wait to try this myself.

On Tue, Mar 26, 2013 at 9:36 AM, Eugen Leitl <eugen at leitl.org> wrote:

> http://www.newscientist.com/article/dn23309-information-superhighway-approaches-light-speed.html
> Information superhighway approaches light speed
> 18:00 24 March 2013 by Jacob Aron Nothing moves faster than light in a
> vacuum, but large volumes of data can now travel at 99.7 per cent of this
> ultimate speed limit.
> In glass optical fibres, light travels 31 per cent slower than in a vacuum.
> Hollowing them out so that most of the light travels through air speeds
> things up. But these hollow fibres are a poor replacement as light scatters
> at the glass-air interface, limiting the number of wavelengths, and
> therefore
> the volume of data, transmitted at once.
> Now Francesco Poletti and colleagues at the University of Southampton, UK,
> have made fibres with an ultra-thin glass rim, enabling a much wider band
> of
> wavelengths to travel at high speed at once. The team's record is a 73.7
> terabit per second transmission over 310?metres, a 15,000-fold increase
> over
> ordinary hollow fibres.
> "Previous fibres either have higher bandwidth but high loss, or lower loss
> but narrower bandwidth," says Poletti. "We've achieved both in the same
> fibre."
> Journal reference: Nature Photonics, DOI: 10.1038/nphoton.2013.45
> http://www.nature.com/nphoton/journal/vaop/ncurrent/full/nphoton.2013.45.html
> Towards high-capacity fibre-optic communications at the speed of light in
> vacuum
> F. Poletti,      N. V. Wheeler,  M. N. Petrovich,        N. Baddela,     E.
> Numkam Fokoua,   J. R. Hayes,    D. R. Gray,     Z. Li,  R. Slav?k       &
> D.
> J. Richardson Nature Photonics (2013) doi:10.1038/nphoton.2013.45
> Received 13 September 2012 Accepted 08 February 2013 Published online 24
> March 2013
> Abstract
> Wide-bandwidth signal transmission with low latency is emerging as a key
> requirement in a number of applications, including the development of
> future
> exaflop-scale supercomputers, financial algorithmic trading and cloud
> computing1, 2, 3. Optical fibres provide unsurpassed transmission
> bandwidth,
> but light propagates 31% slower in a silica glass fibre than in vacuum,
> thus
> compromising latency. Air guidance in hollow-core fibres can reduce fibre
> latency very significantly. However, state-of-the-art technology cannot
> achieve the combined values of loss, bandwidth and mode-coupling
> characteristics required for high-capacity data transmission. Here, we
> report
> a fundamentally improved hollow-core photonic-bandgap fibre that provides a
> record combination of low loss (3.5 dB km?1) and wide bandwidth (160 nm),
> and
> use it to transmit 37 ? 40 Gbit s?1 channels at a 1.54 ?s km?1 faster speed
> than in a conventional fibre. This represents the first experimental
> demonstration of fibre-based wavelength division multiplexed data
> transmission at close to (99.7%) the speed of light in vacuum.