Tag: Quantum

Boffins to build real large scale quantum computer

schrodingers_catAn international team, led by a scientist from the University of Sussex, has today unveiled the first practical blueprint for how to build a quantum computer.

Powered by cats who may, or may not be dead, the computer will be the most powerful on Earth and has calculated the existence of rice pudding even before it has been built.

According to the journal Science Advances, which we get for the spot the quark competition, the blueprint includes a new invention which uses connections created by electric fields that allow charged atoms (ions) to be transported from one module to another. This new approach allows 100,000 times faster connection speeds between individual quantum computing modules compared to current state-of-the-art fibre link technology.

Previously, scientists thought of using fibre optic connections to connect individual computer modules.

The project’s top boffin Prof Winfried Hensinger, head of Ion Quantum Technology Group at the University of Sussex said the availability of a universal quantum computer may have a fundamental impact on society.

“Without doubt it is still challenging to build a large-scale machine, but now is the time to translate academic excellence into actual application building on the UK’s strengths in this ground-breaking technology. I am very excited to work with industry and government to make this happen.”

The computer’s possibilities for solving, explaining or developing could be endless. However, its size will be anything but small. The machine is expected to fill a large building, consisting of sophisticated vacuum apparatus featuring integrated quantum computing silicon microchips that hold individual charged atoms (ions) using electric fields.

Still anything that involves getting dead cats to do the ioning is almost certain to be a winner.



Boffins build quantum bridge out of diamonds

Chinas-sky-bridgeBoffins have built a quantum bridge out of diamonds.

Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge by forcefully embedding two silicon atoms in a diamond matrix.

Sandia researcher Ryan Camacho said it was possible that the first useful quantum computer may be a  connected cluster of small ones.

Distributing quantum information on a bridge, or network, could also enable novel forms of quantum sensing, since quantum correlations allow all the atoms in the network to behave as though they were one single atom.

The joint work with Harvard University used a focused ion beam implanter at Sandia’s Ion Beam Laboratory designed for blasting single ions into precise locations on a diamond substrate.

According to Science magazine, Sandia researchers Ed Bielejec, Jose Pacheco and Daniel Perry used implantation to replace one carbon atom of the diamond with the larger silicon atom, which crowds out the two carbon atoms on either side of the silicon atom and forces them to escape.

Though the silicon atoms are embedded in a solid, they behave as though floating in a gas, and their electrons’ response to quantum stimuli are not clouded by unwanted interactions anything else.

Camacho said: “We can create thousands of implanted locations, which all yield working quantum devices, because we plant the atoms well below the surface of the substrate and anneal them in place. Before this, researchers had to search for emitter atoms among about 1,000 randomly occurring defects—that is, non-carbon atoms—in a diamond substrate of a few microns to find even one that emitted strongly enough to be useful at the single photon level.”

Once the silicon atoms settle in the diamond substrate, laser-generated photons bump silicon electrons into their next higher atomic energy state. When the electrons return to the lower energy state, because all things seek the lowest possible energy level, they spit out quantised photons that carry information through their frequency, intensity and the polarisation of their wave.

Sandia researcher John Abraham and other Sandia researchers developed special detectors—metal films atop the diamond substrate—that showed the ion beam implants were successful by measuring the ionization signal produced by single ions.

Apparently no cats needed to be harmed in the experiments.

Boffins find a new type of light

dsotmResearchers have decided that we don’t have enough types of light and have come up with another one which they say will be better for quantum computers.

The new light is produced by binding photons to individual electrons and is not the sort of thing that will help you find your way to the loo in the middle of the night.

Vincenzo Giannini  from the Imperial College London in the UK said that the results of this research will have a huge impact on the way we conceive light.  In case we want to do it in ways which do not just involve turning on a light switch.

In 2007 boffins  discovered class of materials called topological insulators, they modelled the behaviour of light as it flashed across the surface. They found that not only could the photons interact with a single electron in this material, but the result would actually combine the properties of both.

These topological insulators are a unique type of material that won’t conduct an electric current through the bulk of their structure, but will carry one along the surface. The UK physicists modelled a single nanoparticle – a tiny sphere less than 0.00001 millimetres in diameter – made from a topological insulator. This allowed them to simulate what would happen if a flash of light beamed across the nanoparticle and collided with its single electron.

Basically they could control what the light was doing and this is the key to creating a the world’s first viable quantum computer. Quantum processors are made of qubits, which can be a ‘1’, ‘0’, or both at the same time – a state known as ‘superposition’. The problem with observing superposition is that physicists have to work with supercooled molecules chilled to a fraction of a degree above absolute zero, and this is expensive and difficult to set up.

But combined photon-electron could allow researchers see the behaviour at room temperature. All they have to do is actually build it in the lab.


IBM creates cloud based quantum computer

schrodingers_catIBM unveiled the world’s first cloud based quantum computer which means that anyone can run quantum computing experiments from anywhere in the world.

Jerry Chow, IBM’s Manager of Experimental Quantum Computing Group said that IBM’s effort gives access to a much broader and larger space of computations.

“It’s a web-based platform for public to access to run quantum algorithm and quantum circuits on a real quantum processor in our labs. We want people to programme their own algorithms and learn what it means to do quantum computing.”

IBM’s cloud-based quantum computer will have just 5 Qbits and one quantum processor rather than an array. IBM plans to add qubits and even change processor configurations over time, but it will not be superfast.

According to Chow, IBM’s custom-built quantum processor is a silicon wafer etched with super-conducting metal which has to be super-cooled to 0.015 degrees above absolute zero.

Chow’s team has set up a queuing system and even a sort of virtual currency, called Q-Coins. Everyone who registers gets coins and can earn more by completing tutorials. The coins are used to run the tests against the Quantum silicon and get replenished when the experiment is done.

The IBM Quantum Computing Cloud interface includes tabs for a underguide and a place to keep track of your results.

Access to the real quantum computer will also reveal errors or “noise in the system,” which can help programmers refine their quantum algorithms. The environment will also include a simulator that will let you compare your results to those from the hardware or simply practice running error-free quantum algorithms.

Aspiring quantum computer scientists can access IBM’s Quantum computer here.

Russian boffins create two qubit quantum circuit

schrodingers_catRussian researchers have emerged from their labs smelling of potentially dead or alive cats after successfully testing Russia’s first superconducting, two-qubit, feedback-controlled circuit.

The research group from MIPT’s Artificial Quantum System Lab and Collective Use Centre had so far manged to develop a single qubit along with a parameter measuring circuit. Alexey Dmitriyev, a postgraduate at AQS said that in the the last six months, MIPT’s lab has done substantial and laborious work to organise the measuring process of superconducting qubits.

“MIPT currently has the necessary infrastructure and human capacity to deliver on building advanced qubit systems,” he said.

Dmitry Negrov, Deputy Head at the Collective Use Centre, added: “We now are at the stage where system parameters are close to the designed conditions. The next step is to take vital measurements, such as coherence time, and refine the qubit bonding. We aim to continue our work on these parameters in the future.”

Of course they are still a long way from actually getting a quantum PC which will run Windows or even solitaire, but they are getting there.

According to Andrey Baturin, Head of Scientific Management at MIPT, quantum technology research is one of the long-term priorities on the institute’s research agenda. “The Artificial Quantum System Lab and Collective Use Centre succeeded in obtaining unique equipment—modern lithographic machines and evaporation units for full-cycle production of qubits and, later, qubit systems; measuring equipment and ultra-low temperature cryostats that allow us to work with qubits at the milli-Kelvin temperature range. Such low temperatures are essential due to the extreme fragility of quantum states that can easily fail from interaction with the outside environment,” says Baturin.

Quantum computer could kill encryption

funny-pictures-cat-hunting-miceMIT has created the first five-atom quantum computer with the potential to crack the security of traditional encryption schemes – if the cat can be bothered getting out of the box and chasing the numbers,

Quantum computing relies on atomic-scale units, or “qubits,” that can be simultaneously 0 and 1. It typically takes about 12 qubits to factor the number 15, but researchers at MIT and the University of Innsbruck in Austria have found a way to pare that down to five qubits, each represented by a single atom.

By using laser pulses to keep the quantum system stable by holding the atoms in an ion trap, the new system promises scalability as well, as more atoms and lasers can be added to build a bigger and faster quantum computer able to factor much larger numbers.

However that tiggers factorisation-based methods such as RSA, used for protecting credit cards, state secrets and other confidential data. This is because they are based on Shor’s algorithm, the most complex quantum algorithm known to date. Fifteen is the smallest number that can meaningfully demonstrate Shor’s algorithm. But this computer returned the correct factors with a confidence better than 99 percent.

Isaac Chuang, professor of physics and professor of electrical engineering and computer science at MIT said that Shor’s algorithm is the most complex quantum algorithm known to date and it is now possible to go to a lab and build a computer which can crack it.

“It might still cost an enormous amount of money to build—you won’t be building a quantum computer and putting it on your desktop anytime soon—but now it’s much more an engineering effort, and not a basic physics question,” Chuang added.

At the moment the MIT machine scalable enough but that is another engineering problem which will be fixed. Once the apparatus can trap more atoms and more laser beams can control the pulses there is no physical reason why that is not going to be in the cards.

Already though that does mean that nation states probably don’t want to publicly store your secrets using encryption that relies on factoring as a hard-to-invert problem. As quantum computers start coming out those old secrets will be unencrypted, Chuang said.

Redmond creates quantum proof encryption

atomium-BelgiumSoftware King of the World Microsoft has invented a form of encryption which it says will defend users from quantum computers.

The only problem is that quantum computers have not been invented yet so we will have to take Microsoft’s word on it that its encryption is safe.

Quantum computers deliver immense power that would be useful in many fields—but potentially break the strongest forms of encryption.

Microsoft research voles claim to have upgraded the encryption protocol that secures the Web to resist attacks from quantum computers.

Governments and computing giants like IBM, Microsoft, and Google are working on quantum computers because tapping subtle effects of quantum physics should let them solve in seconds some problems that a conventional machine couldn’t solve in billions of years.

Kryata Svore, who leads a research group working on software for quantum computers at Microsoft’s headquarters in Redmond, Washington, says this was more than just an academic exercise.

“Given that scalable quantum computers are under development, it is crucial to prepare,” she said. “It can take a decade or more for a new cryptographic algorithm—or “primitive”—to be properly tested out and widely deployed, she says. “There is an urgent need to determine other primitives now.”

Surely this is just a matter of bringing in a few footballers.

The new quantum-proof version of TLS generates encryption keys using a different mathematical problem that’s believed to be beyond the practical reach of both conventional and quantum computers.

That system was tested by using it to encrypt data moving between two PCs, one taking the role of a Web browser and the other a Web server.

The quantum-proof encryption protocol moved data 21 percent more slowly than a version using elliptic curve cryptography, as some websites do today, but the researchers consider that penalty a reasonable one to pay if their idea is polished up for real-world use.

Aussies leap last quantum computer hurdle

high-resolution-kangaroo-hd-wallpapers-new-fresh-images-of-kangaroo-animals-free-download-desktop-background-photosElectrical engineers at the University of New South Wales claim to have cleared one of the last hurdles to building a simple quantum computer.

The researchers have reported this missing piece in the journal Science Advances which we get for the spot the quantum boomerang competition.

Project leader Andrea Morello said that the whole thing was a bit like a Lego box – you can start building up a large architecture by piecing its components together.

Then we guess it breaks and you have a quantum bit on the floor which you tread on in the dead of night when you get up for a glass of water.

Morello and his colleagues have so far been perfecting its basic element, the “quantum bit”. This is a single phosphorus atom entombed in a silicon crystal. Using a carefully tuned magnetic field, the researchers can manipulate the atom’s quantum “spin”, flipping it up or down.

A quantum computer is “not just a ‘faster’ computer,” Morello says. “They are the equivalent of a jet plane to a bicycle.”

Last year the team showed they can write, read and store the spin of a single quantum bit with better than 99.99% accuracy using a magnetic field.

But to carry out complex calculations, a quantum computer needs thousands, or even millions of quantum bits, that can all be individually controlled.

In their latest work, carried out by experimental physicist Arne Laucht, Morello and his team found a way to control each quantum bit using a simple electrical pulse and flooding the whole device with a single magnetic field.

By timing their electrical pulses, the team can tune the phosphorus atom in and out of the oscillating magnetic field, and so flip the phosphorus atom’s spin into any position they want – up, down or an intermediate superposition – without affecting its neighbours.
Kane cautions that we are still a long way from large-scale quantum computing in silicon but he thinks that large-scale silicon quantum computing will become a reality, but there is still a long, steep road ahead.

The group is already at work on these challenges. Morello is confident they will have all the elements in place to build a small-scale test-system within 10 years.

No cats were harmed during testing.

Researchers kill computer circuit size limits

A team of researchers has found a way to kill the size limits on computer circuits by using room-temperature nanotube quantum-tunnelling.

Yoke Khin Yap of Michigan Technological University has been penning a treatise on a possible technique which has been published in the journal Advanced Materials.

The world of transistors and semiconductors in computer processors could give way to systems built on the way electrons misbehave.

Rather than relying on a predictable flow of electrons of current circuits, the new approach depends on quantum tunnelling. In this, electrons travel faster than light and appear to arrive at a new location before having left the old one, and pass straight through barriers that should be able to hold them back. This appears to be under the direction of a cat which is possibly dead and alive at the same time, but we might have gotten that bit wrong.

There is a lot of good which could come out of building such a computer circuit. For a start, the circuits are built by creating pathways for electrons to travel across a bed of nanotubes, and are not limited by any size restriction relevant to current manufacturing methods.

They would require far less power than even the tiniest transistors, and do not give off heat or leak electricity as waste products.

Yap wrote that circuits based on quantum tunnelling could replace silicon with nanotubes made of boron nitride and electrical pathways consisting of quantum dots, in the form of carefully placed bits of gold as small as three nanometers across.

Yap’s team discovered that running the right voltage of current across gold-decorated boron nitride nanotubes allowed electrons to tunnel precisely from one quantum dot to the other, even without the restraining effect of traditional transistor circuits.

The electrons hopped between the gold stepping stones one electron at a time. Since every electron passed the same way, the device is always stable.

What is more important is that Yap’s designs can do all this at room temperature, which makes the technology more suitable for future computer designs.

Yap has already filed for an international patent that would allow the technology to be controlled and licensed for commercial development, although this could be years away from being enacted. 

Los Alamos runs quantum internet

Researchers at Los Alamos National Labs have been running a quantum internet for the last two and a half years, according to Technology Review.

It has been a holy grail of security experts to create a quantum internet that allows perfectly secure communication based on quantum mechanics.

The big idea is that if you measure a quantum object, such as a photon, it is always changed. In a quantum internet any attempt to eavesdrop on a quantum message will leave telltale signs of snooping.

This means that anybody can send a “one-time pad” over a quantum network which can then be used for secure communication using normal email. The user is sure that the cryptography key is secure and not been tampered with. Since it is only used once, there is no change of a hacker knowing what the key is, unless they are a cat which is potentially dead and alive at the same time. Fortunately these are quite rare.

Some forms of quantum networking have been around for a while, but they are limited by the fact that they can only be point-to-point connections over a single length of fibre.

This means that they can only send secure messages directly and cannot be routed.

What Richard Hughes and his mates at Los Alamos National Labs in New Mexico have revealed is that they have been running an alternative quantum internet for two and half years.

This uses a quantum network based around a hub and spoke-type network. All messages get routed from any point in the network to another via this central hub.

So as long as the hub is secure, then the network should also be secure.

While this idea has been thought of, it has been difficult to scale, Los Alamos got around this problem by equipping each node with quantum transmitters. Only the hub is capable of receiving a quantum message but all nodes can send and receiving conventional messages in the normal way.

This means that the entire network is secure, and scalable provided that the central hub is not attacked.

Los Alamos has already designed and built plug-and-play type modules that are about the size of a box of matches so that it will not cripple any network.

The big idea is to eventually have a modules built in to almost any device connected to a fibre optic network, such as set top TV boxes, home computers and so on, to allow perfectly secure messaging.