Tag Archives: quantum

Scientists make quantum leap in developing faster computers

The researchers have created components that could one day be used to develop quantum computers – devices based on molecular scale technology instead of and which would be much faster than conventional computers.

The study, by scientists at the Universities of Manchester and Edinburgh and published in the journal Nature, was funded by the European Commission.

Scientists have achieved the breakthrough by combining with molecular machines that can shuttle between two locations without the use of external force. These manoeuvrable magnets could one day be used as the basic component in quantum computers.

Conventional computers work by storing information in the form of bits, which can represent information in binary code – either as zero or one.

Quantum computers will use quantum , or , which are far more sophisticated – they are capable of representing not only zero and one, but a range of values simultaneously. Their complexity will enable quantum computers to perform intricate calculations much more quickly than conventional computers.

Professor David Leigh, of the University of Edinburgh’s School of Chemistry, said: “This development brings super-fast, non-silicon based computing a step closer.


Most powerful ever quantum chip undergoing tests

QUANTUM computing for the masses could come a step closer if tests prove successful on a prototype chip designed to process more quantum data than any previous device.

Quantum computers have the potential to be vastly more powerful than conventional machines because they exploit the rules of quantum mechanics to perform many calculations in parallel. They are difficult to build, however, because quantum information is easily destroyed. The most powerful machines to date can cope with only a handful of quantum bits, or qubits, making them little more capable than a hand-held calculator.

In contrast, the prototype chip built by D-Wave Systems in Burnaby, British Columbia, Canada, is designed to handle 128 qubits of information. The data is stored in 128 superconducting niobium loops as either a clockwise or an anticlockwise current, representing a 0 or a 1, or as a qubit with both currents at the same time in a quantum superposition. When the information needs to be processed, the individual qubits are manipulated by a magnetic field. To make the entire chip superconduct so that the currents can flow indefinitely without dissipating heat, it is cooled to 0.01 °C above absolute zero.

Because superconducting circuits are relatively large, they are easier to manufacture than other types of quantum devices, which manipulate single electrons or photons and so need to be much smaller. “It can be built using standard semiconductor approaches,” says Geordie Rose, chief technology officer of D-Wave. In addition, the method of computation, called adiabatic computing, does not use logic gates, further simplifying the design.


Levitation At Microscopic Scale Could Lead To Nanomechanical Devices Based On Quantum Levitation

Magicians have long created the illusion of levitating objects in the air. Now researchers have actually levitated an object, suspending it without the need for external support. Working at the molecular level, the researchers relied on the tendency of certain combinations of molecules to repel each other at close contact, effectively suspending one surface above another by a microscopic distance.

Researchers from Harvard University and the National Institutes of Health (NIH) have measured, for the first time, a repulsive quantum mechanical force that could be harnessed and tailored for a wide range of new nanotechnology applications.

The study, led by Federico Capasso, Robert L. Wallace Professor of Applied Physics at Harvard’s School of Engineering and Applied Science (SEAS), will be published as the January 8 cover story of Nature.

The discovery builds on previous work related to what is called the Casimir force. While long considered only of theoretical interest, physicists discovered that this attractive force, caused by quantum fluctuations of the energy associated with Heisenberg’s uncertainty principle, becomes significant when the space between two metallic surfaces, such as two mirrors facing one another, measures less than about 100 nanometers.


Quantum computers could excel in modeling chemical reactions

Quantum computers would likely outperform conventional computers in simulating chemical reactions involving more than four atoms, according to scientists at Harvard University, the Massachusetts Institute of Technology, and Haverford College. Such improved ability to model and predict complex chemical reactions could revolutionize drug design and materials science, among other fields.

Writing in the Proceedings of the National Academy of Sciences, the researchers describe “software” that could simulate chemical reactions on quantum computers, an ultra-modern technology that relies on quantum mechanical phenomena, such as entanglement, interference, and superposition. Quantum computing has been heralded for its potential to solve certain types of problems that are impossible for conventional computers to crack.

“There is a fundamental problem with simulating quantum systems — such as chemical reactions — on conventional computers,” says Alán Aspuru-Guzik, assistant professor of chemistry and chemical biology in Harvard’s Faculty of Arts and Sciences. “As the size of a system grows, the computational resources required to simulate it grow exponentially. For example, it might take one day to simulate a reaction involving 10 atoms, two days for 11 atoms, four days for 12 atoms, eight days for 13 atoms, and so on. Before long, this would exhaust the world’s computational power.”

Unlike a conventional computer, Aspuru-Guzik and his colleagues say, a quantum computer could complete the steps necessary to simulate a chemical reaction in a time that doesn’t increase exponentially with the reaction’s complexity.


World first for sending data using quantum cryptography

For the first time the transmission of data secured by quantum cryptography is demonstrated within a commercial telecommunications network. 41 partners from 12 European countries, including academics from the University of Bristol, have worked on realising this quantum cryptographic network since April 2004.

Today [Wednesday 8 October] the first commercial communication network using unbreakable encryption based on quantum cryptography is demonstrated in Vienna, Austria. In particular the encryption utilises keys that are generated and distributed by means of quantum cryptographic technologies. Potential users of this network, such as government agencies, financial institutions or companies with distributed subsidiaries, can encrypt their confidential communication with the highest level of security using the quantum cryptographically generated keys.

The network consists of six nodes and eight intermediary links with distances between 6km and 82km (seven links utilising commercial standard telecommunication optical fibres and one “free-space”-link along a line of sight between two telescopes). The links employ altogether six different quantum cryptographic technologies for key generation which are integrated into the network over standardised interfaces.

The network is installed in a standard optical fibre communication ring provided by SECOQC partners, Siemens AG Österreich in Vienna. Five subsidiaries of Siemens are connected to the network. The operation of the quantum cryptographic network will be visualised on a screen at the Siemens Forum in Vienna and streamed live over the Internet. The network-wide key generation and distribution will be demonstrated, the different functionalities of the network itself will be presented as well as utilisation of the keys for standard communication applications. A voice-over-iptelephone-application will be secured by the information-theoretically secure “one-time-pad-encryption“ while videoconferencing will be protected by symmetrical AES-encryption with frequent key changes. A low-cost key distributor, with the potential of extending the quantum cryptographic network to the consumer, will also be shown.


Intel touts progress toward intelligent computers

I hope Intel warned the Luddites and pessimists away at the door, because the chipmaker had a lot of bullish statements Thursday about its belief that computers will become smarter than humans.

At the Intel Developer Forum here, Intel Chief Technology Officer Justin Rattner showed off a number of technologies in computing, robotics, and communication that he cited as evidence that Ray Kurzweil’s concept of “singularity,” when machine intelligence surpasses human intelligence, is impending. Demonstrations spotlighted the wireless transmission of electrical power, dextrous robots with new sensory abilities, a direct interface to the brain, programmable materials that can be used for shape-shifting devices such as resizable cell phones, and silicon photonics that enables chips to communicate with photons rather than electrons.

“We’re making steady progress toward Ray Kurzweil’s singularity,” Rattner said.

Intel of course remains at its heart a chipmaker, and Rattner began with a brief tour, assisted by Mike Garner, senior technologist for Intel’s emerging materials group, of various successors to the current complimentary metal oxide semiconductor (CMOS) process used to make processors. Future ideas that pack ever more computing capacity into a given volume include spintronics, quantum computing, carbon nanotubes.

It’s good to see a big name such as Intel take seriously Kurzweil’s ideas on accelerating progress, the Singularity, etc.

The more people are working towards a common goal, the better.

Quantum computing breakthrough

In a Nature Physics journal paper currently online, the researchers describe how they have created a new, hybrid molecule in which its quantum state can be intentionally manipulated – a required step in the building of quantum computers.

“Up to now large-scale quantum computing has been a dream,” says Gerhard Klimeck, professor of electrical and computer engineering at Purdue University and associate director for technology for the national Network for Computational Nanotechnology.

“This development may not bring us a quantum computer 10 years faster, but our dreams about these machines are now more realistic.”

The workings of traditional computers haven’t changed since they were room-sized behemoths 50 years ago; they still use bits of information, 1s and 0s, to store and process information. Quantum computers would harness the strange behaviours found in quantum physics to create computers that would carry information using quantum bits, or qubits. Computers would be able to process exponentially more information.

If a traditional computer were given the task of looking up a person’s phone number in a telephone book, it would look at each name in order until it found the right number. Computers can do this much faster than people, but it is still a sequential task. A quantum computer, however, could look at all of the names in the telephone book simultaneously.

Quantum computers also could take advantage of the bizarre behaviours of quantum mechanics – some of which are counterintuitive even to physicists – in ways that are hard to fathom. For example, two quantum computers could, in concept, communicate instantaneously across any distance imaginable, even across solar systems.


New Technology Making Brain Tumor Surgery Less Risky

Brain specialists at The Neuroscience Institute at University Hospital and the University of Cincinnati have taken a significant step forward in their quest to treat difficult tumors while preserving areas of the brain that are responsible for speech and movement. The Cincinnati specialists are among the first in the country to use new technology that integrates functional MRI (fMRI) data into high-tech surgical navigation systems.The fMRI data, which pinpoint language, cognition, and mobility centers of the brain, allow neurosurgeons to remove tumors to the greatest extent possible without harming areas that are critical to the patient’s quality of life.

Functional MRI creates a series of images that capture blood oxygen levels in parts of the brain that are responsible for movement, perception, and cognition. Functional MRI, which reveals the brain in action, differs from standard MRI, which provides a static image.

“This is a quantum leap in what we’re able to do,” said Dr. James Leach, a brain-imaging specialist (neuroradiologist) with UC Radiology and The Neuroscience Institute. “It has significantly affected how neurosurgeons plan to do neurosurgery and how much tumor they can remove while still avoiding critical areas of brain function.”


Scientists Scan Striking Nanoscale Images

Scientists Scan Striking Nanoscale Images


For the first time, late last year, a team of British scientists filmed the nanoscale interaction of an attacking virus with an enzyme and a DNA strand in real time.

This was the latest breakthrough in the advancement of scanning probe microscopes — the family of nonoptical microscopes researchers use to create striking images through raster scans of individual atoms.

The granddaddy of them all is the scanning tunneling microscope, a 1986 invention that won its creators the Nobel Prize. STMs pass an electrical probe over a substance, allowing scientists to visualize regions of high electron density and infer the position of individual atoms and molecules.

To mark the 25th anniversary of the development of STMs, an international contest — SPMage07 — showcasing the best STM images was founded.

Turning ‘funky’ quantum mysteries into computing reality

Turning ‘funky’ quantum mysteries into computing reality

The strange world of quantum mechanics can provide a way to surpass limits in speed, efficiency and accuracy of computing, communications and measurement, according to research by MIT scientist Seth Lloyd.

Quantum mechanics is the set of physical theories that explain the behavior of matter and energy at the scale of atoms and subatomic particles. It includes a number of strange properties that differ significantly from the way things work at sizes that people can observe directly, which are governed by classical physics.

“There are limits, if you think classically,” said Lloyd, a professor in MIT’s Research Laboratory of Electronics and Department of Mechanical Engineering. But while classical physics imposes limits that are already beginning to constrain things like computer chip development and precision measuring systems, “once you think quantum mechanically you can start to surpass those limits,” he said.

Lloyd will be speaking about this research at the American Association for the Advancement of Science annual meeting in Boston, on Saturday, Feb. 16, in a session on Quantum Information Theory.

“Over the last decade, a bunch of my colleagues and postdocs and I have been looking at how quantum mechanics can make things better.” What Lloyd refers to as the “funky effects” of quantum theory, such as squeezing and entanglement, could ultimately be harnessed to make measurements of time and distance more precise and computers more efficient. “Once you open your eyes to the quantum world, you see a whole lot of things you simply cannot do classically,” he said.

Among the ways that these quantum effects are beginning to be harnessed in the lab, he said, is in prototypes of new imaging systems that can precisely track the time of arrival of individual photons, the basic particles of light. “There’s significantly greater accuracy in the time-of-arrival measurement than what one would expect,” he said. And this could ultimately lead to systems that can detect finer detail, for example in a microscope’s view of a minuscule object, than what were thought to be the ultimate physical limitations of optical systems set by the dimensions of wavelengths of light.