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Primeur weekly 2016-10-24

Focus

EUDAT Project Director Damien Lecarpentier to expand on added value of EUDAT for data storage, the success of the first DI4R Conference and on the importance of Key Performance Indicators for e-infrastructures ...

Quantum computing

Exploring defects in nanoscale devices for possible quantum computing applications ...

Quantum computers: 10-fold boost in stability achieved ...

New 3D wiring technique brings scalable quantum computers closer to reality ...

Focus on Europe

ISC 2017 seeks contributors for Conference programme ...

Middleware

Allinea brings new software performance briefings to SC16 ...

Hardware

Innovative technique for shaping light could solve bandwidth crunch ...

R&D collaboration in integrated electronic systems receives top award ...

UK Met Office installs new HPC system to significantly improve productivity of weather and climate data analysis ...

Fast data sharing with South Korea via Netherlight ...

NSF funds new projects to advance energy-efficient computing ...

Applications

Can we find more benign nanomaterials? ...

Scientists find technique to improve carbon superlattices for quantum electronic devices ...

A new class of materials could realize quantum computers ...

Rhön-Klinikum Hospitals to study how IBM Watson can support doctors in the diagnosis of rare diseases ...

Predicting jellyfish invasions at coastal power stations ...

IBM and Quest Diagnostics launch Watson-powered genomic sequencing service to help physicians bring precision cancer treatments to patients nationwide ...

A new spin on superconductivity ...

Insilico Medicine to present on recent advances in AI at BioData World in Cambridge ...

Unraveling the science behind biomass breakdown ...

T-rays will speed up computer memory by a factor of 1,000 ...

Promise of gene therapy for glaucoma shines bright in award-winning image ...

The Cloud

Amazon Web Services Cloud now available to customers from data centres in Ohio ...

IBM Cloud expands Bluemix ecosystem in China to fuel blockchain and IoT innovation ...

Atos teams with VMware to launch Digital Private Cloud offering ...

DNAstack launches genomics platform to accelerate disease research and precision medicine ...

Innovative technique for shaping light could solve bandwidth crunch


Researchers used more than 100 spatial modes of light to transmit an image pixel by pixel over a lab-based free-space optical network. Credit: Carmelo Rosales-Guzman, University of Witwatersrand.
19 Oct 2016 Washington - As data demands continue to grow, scientists predict that it's only a matter of time before today's telecommunication networks reach capacity unless new technologies are developed for transporting data. A new technique could help avert this bandwidth crunch by allowing light-based optical networks to carry more than one hundred times more data than is possible with current technologies.

Laser light comes in many different shapes, or spatial modes. However, today's optical networks use just one spatial mode to carry information, limiting the amount of data that can be transmitted at one time. Researchers led by Andrew Forbes, a professor at the University of Witwatersrand, South Africa, developed a technique known as spatial multiplexing that reshapes a laser beam into many spatial modes that can each carry information.

In a paper presented at the OSA Laser Congress in Boston, the researchers demonstrate optical communication with more than 100 spatial modes by combining their new spatial multiplexing approach with wavelength division multiplexing (WDM), which uses different wavelengths of light to carry information.

"We created 35 spatial modes encoded in three different wavelengths, producing 105 total modes", stated Carmelo Rosales-Guzmán, research fellow and first author of the paper. "Our new method might serve as the basis for future communication technologies."

The researchers demonstrated that their technique can transmit data with 98 percent efficiency in a laboratory free-space optical network, which uses light to transmit information over the air. The scientists say the approach should also work in optical fibers, the basis for fiber-optic communications.

The new technique makes use of light with an orbital angular momentum, which gives it a twisted, or helical, shape. Different spatial modes can be created by varying the number of twists, known as the azimuthal degrees of freedom. While other scientists have been exploring the use of azimuthal degrees of freedom for increasing bandwidth, recent research showed that even though, in theory, the set of modes with orbital angular momentum is infinite, in practice there aren't enough modes available to make significant improvements.

Andrew Forbes' team solved this problem by using the azimuthal degrees of freedom plus another variable known as a radial degree of freedom. Each azimuthal degree of freedom can have, in theory, an infinite amount of radial degrees of freedom, but there are practical limitations that restrict this number. Because all the modes are orthogonal to each other, the signals don't get mixed up as they travel and can be separated upon arrival at their destination. The researchers say that this is the first time two spatial degrees of freedom have been used to optically encode information.

Key to this new approach is an optical device known as a spatial light modulator. The researchers used one spatial light modulator to shape the laser light into the various modes and another to reverse the process on the receiving end.

"One of the advantages of our approach is that we only need a single detector to demultiplex all the spatial modes to recover all the information", stated Carmelo Rosales-Guzmán. "This is faster than other approaches for increasing bandwidth that need multiple detectors."

To test the new technique, the researchers used it to encode a grayscale and colour image. Each image was sent across a communication link pixel by pixel and then each pixel was recovered to reconstruct the image. For the grayscale image, each gray level was linked to a separate spatial mode, allowing transmission of 105 gray levels.

"In this demonstration, sending a 10,000-pixel image took 5 to 7 minutes", stated Carmelo Rosales-Guzmán. "However we could increase that speed by sending two or four pixels at the same time or by using many more wavelengths."

Real-world free-space optical networks - which can transfer information between buildings, for example - come with many challenges that aren't present in the lab. As a next step, the researchers are partnering with experts in free-space communication to adapt their technique for practical applications.

"We are working with a company in South Africa that already makes a device that has the ability to use different spatial modes for free space communication", stated Carmelo Rosales-Guzmán. "We are interested in trying to increase the bandwidth of their device to four times what it is capable of now."

Source: The Optical Society

Back to Table of contents

Primeur weekly 2016-10-24

Focus

EUDAT Project Director Damien Lecarpentier to expand on added value of EUDAT for data storage, the success of the first DI4R Conference and on the importance of Key Performance Indicators for e-infrastructures ...

Quantum computing

Exploring defects in nanoscale devices for possible quantum computing applications ...

Quantum computers: 10-fold boost in stability achieved ...

New 3D wiring technique brings scalable quantum computers closer to reality ...

Focus on Europe

ISC 2017 seeks contributors for Conference programme ...

Middleware

Allinea brings new software performance briefings to SC16 ...

Hardware

Innovative technique for shaping light could solve bandwidth crunch ...

R&D collaboration in integrated electronic systems receives top award ...

UK Met Office installs new HPC system to significantly improve productivity of weather and climate data analysis ...

Fast data sharing with South Korea via Netherlight ...

NSF funds new projects to advance energy-efficient computing ...

Applications

Can we find more benign nanomaterials? ...

Scientists find technique to improve carbon superlattices for quantum electronic devices ...

A new class of materials could realize quantum computers ...

Rhön-Klinikum Hospitals to study how IBM Watson can support doctors in the diagnosis of rare diseases ...

Predicting jellyfish invasions at coastal power stations ...

IBM and Quest Diagnostics launch Watson-powered genomic sequencing service to help physicians bring precision cancer treatments to patients nationwide ...

A new spin on superconductivity ...

Insilico Medicine to present on recent advances in AI at BioData World in Cambridge ...

Unraveling the science behind biomass breakdown ...

T-rays will speed up computer memory by a factor of 1,000 ...

Promise of gene therapy for glaucoma shines bright in award-winning image ...

The Cloud

Amazon Web Services Cloud now available to customers from data centres in Ohio ...

IBM Cloud expands Bluemix ecosystem in China to fuel blockchain and IoT innovation ...

Atos teams with VMware to launch Digital Private Cloud offering ...

DNAstack launches genomics platform to accelerate disease research and precision medicine ...