Author Archives: Alun Williams

Four lasers conjure fibre optic out of thin air

Professor Howard Milchberg

Professor Howard Milchberg

Optical fibres made from thin air could transmit data to and from hard-to-reach places.

Regular optical fibres are made from two transparent materials that slow light down by different amounts. The difference in materials lets light reflect along the length of the cable without leaking out – perfect for sending a signal over long distances.

But it’s hard to put fibres in some places, like the upper atmosphere or inside nuclear reactors. And signals sent through open air often degrade because the light spreads out.

Now, Howard Milchberg of the University of Maryland, College Park, and his colleagues have come up with a way to mimic a fibre in the air itself.

The team shone four lasers in a square arrangement, heating air molecules and creating a low-density ring around a denser core of air. Light bounces around the dense core just like in a fibre.

The air fibre lasts for a few milliseconds – more than enough to send a signal. “This is an extremely long time from the vantage point of a laser,” says Milchberg. The results are published in the journal Optica.

So far the team has tested air fibres over a range of 1 metre. These delivered a signal 50 per cent stronger than through air alone over the same distance. Sending signals further gives light more chance to spread, so in theory, a 100-metre air-fibre could deliver a signal 1000 times stronger than sending it through air alone.

The team also transmitted a laser with 100 times more energy than those used to make the fibre. And they were able to receive signals: small flashes of light from the other end were detected. This suggests the fibre could be used for remote sensing, which could include detecting explosives at a distance.

Syndicated content: Jacob Aron, New Scientist

Boron buckyballs roll out from Brown University

Boron Ball - Brown University

Boron Ball – Brown University

Score one for boron. For the first time, a version of the famous football-shaped buckyball has been created from boron.

Discovered in 1985, buckyballs are made from 60 carbon atoms linked together to form hollow spheres. The molecular cages are very stable and can withstand high temperatures and pressures, so researchers have suggested they might store hydrogen at high densities, perhaps making it a viable fuel source. At normal pressures, too much of the lightweight gas can escape from ordinary canisters, and compressing it requires bulky storage tanks.

Boron sits next to carbon in the periodic table, so a boron ball may also display useful properties. But it wasn’t clear whether boron could form such structures.

Now Lai-Sheng Wang at Brown University in Providence, Rhode Island, and his colleagues have made a cage-like molecule with 40 boron atoms by vaporising a chunk of boron with a laser then freezing it with helium, creating boron clusters. The team analysed the energy spectra of these clusters and compared them with computer models of 10,000 possible arrangements of boron atoms. The matching configuration revealed they had created the boron ball.

Unlike carbon buckyballs, in which the faces are made of hexagons and pentagons, the boron buckyball is made from triangles, hexagons and heptagons. As a result, it is less spherical but still an enclosed structure. Wang has dubbed the molecule “borospherene”. The team is now hunting for a boron analogue of graphene – a strong sheet of carbon just one atom thick that is often touted as a “wonder” material because of its unique electrical properties.

Mark Fox at Durham University, UK likes the name – and is excited at the prospect of finding a boron version of graphene. Buckyballs led to the discovery of graphene, he says, and history may repeat itself with boron.

Journal reference: Nature Chemistry, DOI: 10.1038/nchem.1999

Syndicated content: Jacob Aron, New Scientist

Image: Wang lab/Brown University

Second batch of O3B comms satellites successfully launched

O3b satellitesFour more O3B satellites have been launched, to help provide telco services in emerging markets.

The Ka-band satellites are positioned at an altitude of 8,063 kilometers – four times closer to the earth than geostationary satellites, notes Thales Alenia Space - and they are intended to support “high speed, low cost, low-latency Internet and telecommunications services”.

“O3b Networks will supply trunking and mobile backhaul connectivity to telecom operators and service providers at speeds comparable to those offered by fiber-optic networks,” says Thales Alenia Space, the prime contractor.

A year ago the first four such satellites were launched, and a third batch will follow.

“Today is an important step towards further completion of the constellation with the launch of the 2nd batch that will be followed by third batch in early 2015,” said Jean Loïc Galle, CEO of Thales Alenia Space.

“We are very proud to be part of this endeavour, with its unprecedented operational and beam flexibility, and its potential to connect billions of people who have, so far, had limited access to broadband”.

The satellites were launched from French Guiana by Arianespace using a Soyouz rocket.

http://www.youtube.com/watch?v=aZIpH7gQ1Rs

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CSR opens new R&D centre in Bristol

CSR opens new R&D centre in Bristol

CSR opens new R&D centre in Bristol

Bluetooth specialist CSR has opened a new R&D facility in Bristol. It will concentrate on wireless connectivity and audio for products in areas such as automotive and wearable devices.

It already had an R&D site at the Bristol & Bath Science Park, since 2012, and the new facility is at Almondsbury in Bristol. The expansion will create a number of job opportunities in the local area, says CSR, especially for graduates from South West universities.

“At CSR, we’re passionate about developing cutting-edge technology that helps our customers turn great ideas into market leading products, and to do that we need to invest strategically in R&D,” said Anthony Murray, senior vp of CSR’s Business Group.

“That’s why we’re opening this new, larger facility in Bristol. Bristol has a vibrant technology scene and with high quality universities that are developing the next generation of engineering talent on our doorstep it is a great place to expand our R&D capabilities.”

Work at the facility will include system engineering, software and digital design and architecture verification.

Biocatch behavioural biometrics promises password obsolescence

Logitech keyboardSoftware can identify people based solely on the way they use their mouse and keyboard, and it could let us do away with passwords altogether, writes Paul Marks of New Scientist.

As we sit hunched over our keyboards, it is hard to believe that the way we peck at the keys and swish the cursor around is unique. But several companies believe this could be used to prove our identity, doing away with one of the most annoying aspects of digital life: passwords.

From e-commerce sites to social media profiles, passwords protect all kinds of sensitive information. But recent security breaches show just how vulnerable the system is. Earlier this year, the Heartbleed bug sent people scurrying to change passwords across a huge swathe of the internet. And in May, eBay announced that over 200 million accounts may have been compromised in a security breach.

This has boosted interest in behavioural biometrics, says Uri Rivner of Biocatch, a firm based in Tel Aviv, Israel. Behavioural biometrics is based on the idea that individuals subconsciously use their mouse and keyboard in predictable ways – and that these behaviours can reliably identify them. Examples of these actions include how quickly a user selects buttons that pop up on screen, how long they hover over menus, how fast they move the mouse and whether they scroll using the cursor keys, the scroll bar or the mouse wheel. Not all of these need to be used, though.

“We don’t need to find behaviours unique to each person on the planet,” says Neil Costigan, CEO of Behaviosec in Luleå, Sweden. “We just need enough of a spread of behaviours to verify that someone is who they say they are. We look at the behaviour to see if it matches that person’s previous behaviour.”

Plenty of companies are already beginning to implement this technology. Biocatch ran successful trials on the networks of two different banks, which it announced on 17 June had helped it to raise $10 million in venture capital funding. In the US, IBM is starting to deploy the technique in online security software it sells to banks. And Behaviosec has been funded by the Pentagon’s research arm, DARPA, to adapt its desktop behavioural biometrics systems to tablets and smartphones.

IBM’s system monitors behaviour only after a person has logged in using their password. This can prevent a fraudster making transactions, pretending to be an authenticated user who has, for example, gone to make coffee without logging out. When behaviours are detected that are out of character, the software will ask them to log in again with some extra security questions.

Biocatch aims to replace passwords entirely, although at the moment its software is also only used after logging in. The system is more active than IBM’s, presenting people with what it calls subconscious “challenges” that garner distinctive responses. For instance, the software makes the cursor disappear for a few seconds and the type of mouse motion people use to recover it – clockwise, anticlockwise, large arc, small arc – is recorded.

Rivner says that by building a model of how individuals respond to these challenges, and then monitoring actions while banking or shopping online, the software can tell within a few keystrokes if the user is the same person who originally logged in. He says this is well on the way to ridding us of the hassle of passwords, PINs, captchas and other login methods.

Similar advances are on the way with mobile technology. Touch behaviours like finger pressure, swipe speed, angles of swipe, gyroscope and accelerometer readings can all be harnessed to authenticate a user, says Costigan. “The smartphone has an amazing array of inputs for behaviour recognition.”

Syndicated content: Paul Marks, New Scientist

Quantum transmission sent through space

The first quantum transmission to go via space paves the way for ultra-secure communications satellites.

Secret encryption keys transmitted via quantum links provide the ultimate way to communicate securely. That’s because any attempt to intercept the key will be revealed thanks to the laws of quantum mechanics, which say that interception will introduce changes that give away eavesdroppers.

The technology is already available for fibre-optic cables, but a truly global network would need satellites to beam quantum data between distant locations. To test how these might work, Paolo Villoresi at the University of Padua in Italy and his colleagues turned to satellites covered in ultra-reflective mirrors. These are normally used to bounce laser beams back to Earth. The time they take to return shows up any shifts in gravity.

In 2007, the team sent a beam of light to space using the Matera Laser Ranging Observatory (MLRO) in Italy and detected single photons bounced off Japan’s Ajisai satellite. For the latest experiment, they prepared photons in four different quantum states – the minimum required to generate an encryption key – and sent them to space using the MLRO. They were able to receive quantum bits of information, or qubits, bounced back from five satellites up to 2600 kilometres above. That smashes the previous record for sending quantum information – 144 kilometres, between two locations on Earth.

To ensure they didn’t count background photons that were not part of the signal, the team timed the laser pulses exactly, rejecting any light that returned outside a narrow time window. The observatory acted as the transmitter and receiver, so the team decided not to send an encrypted message. Still, the team thinks the photons would have been able to encrypt about one bit of data a second.

The team has a way to go before quantum satellites are up to speed. Light travells easily through fibre optic cables compared to turbulent air, so ground-based commercial versions of the technology can encrypt at much faster rates of at least 1 megabit a second.

Villoresi compares the performance to Sputnik, the first-ever satellite, launched in 1957. “Comments at the time were, ‘How nice, the satellite can send a few beeps, it’s totally useless’,” he says. “We are more or less the same level.” But even a very limited data channel could be used to send secure commands to a spacecraft, he says.

Rupert Ursin at the Institute for Quantum Optics and Quantum Information in Vienna, Austria, points out that Villoresi’s team sent the qubits in four bursts, each tens of seconds apart. That means they did not detect all four quantum states at once, which would be necessary for a true quantum satellite.

And Jian-Wei Pan at the University of Science and Technology of China in Hefei notes that a lot of photons are lost in transmission, so he is not sure the signal would be strong enough to transmit a full quantum key. But Pan and Ursin both say the work shows the technology is getting close.

China has announced plans to launch a true quantum communications satellite in 2016, and other nations’ space agencies are investigating the possibility. “Everything is ready, and if we had enough money we could fly,” says Ursin. “The risk that we fail in space is reduced thanks to these kinds of experiments.”

Journal reference: arxiv.org/abs/1406.4051

Syndicated content: Jacob Aron, New Scientist