In the drive to understand and harness quantum effects as they relate to information processing, scientists in Waterloo and Massachusetts have benchmarked quantum control methods on a 12-Qubit system. Their research was performed on the largest quantum information processor to date.
Theorists and experimentalists at the Institute for Quantum Computing and (IQC) and Perimeter Institute for Theoretical Physics (PI) in Waterloo, along with MIT, Cambridge, have presented an operational control method in quantum information processing extending up to 12 qubits. The team's research is available in Physical Review Letters (PRL 96, 170501 week ending 5 May, 2006) and describes the approaches, accuracy and scalability. Despite decoherence, the researchers reached a 12-coherence state and decoded it using liquid state nuclear magnetic resonance quantum information processors.
Raymond Laflamme, Executive Director at the Institute for Quantum Computing and Long Term Researcher at Perimeter Institute says - "…our experiment shows a high level of quantum control over the largest quantum register to date. It is an important step in implementing quantum information processing on larger and larger devices. This is an important milestone towards harnessing the quantum world."
The team's findings set a new algorithmic benchmark in a global effort to exploit quantum properties in order to support entirely new modes of information processing – such as quantum computers with an ability to solve certain types of incredibly complex problems that no modern day computer can approach. The basic principles behind today's computers and other information processing devices (known as "classical" systems) were developed in the 1930s. However, today's theories governing the calculation, storage and transmission of information are at a crossroads. As wires and logic gates become ever smaller, quirky quantum phenomena in the tiny world of atoms take over and impede the efficient flow of information. Select groups of international theorists and experimentalists - including those who are clustering in Waterloo, Ontario - are trying to understand and harness the phenomena and, with this latest research, have set a new standard by controlling a 12-Qubit system.
Observing Quantum Transactions In A Nanotube Excitons are "quasiparticles" created when a photon strikes a semiconductor and excites an electron to a higher energy level. The electron leaves behind a positively charged void called a "hole." That hole pairs with the electron to form the exciton, which takes on a life of its own that ends abruptly when it emits a photon or becomes quenched.
Quantum Bit (qubit) Circuit NEC Corporation, Japan Science and Technology Agency (JST) and the Institute of Physical and Chemical Research (RIKEN) have together successfully demonstrated the world's first quantum bit (qubit) circuit that can control the strength of coupling between qubits. Technology achieving control of the coupling strength between qubits is vital to the realization of a practical quantum computer, and has been long awaited in the scientific field.
Spintronics Technology In 1994, Bandyopadhyay and colleagues were the first group to propose the use of spin in classical computing. Then two years later, they were among the first researchers to propose the use of spin in quantum computing. The recent work goes a long way toward implementing some of these ideas.
Center for Extreme Quantum Information Theory (xQIT) The new center enables a major new push by MIT theorists in the international race to determine the ultimate capabilities of quantum information systems. Establishing these theoretical capabilities would be a step towards being able to exploit quantum effects for novel applications, including computers, communication networks and global positioning systems.
Designing Quantum Computers As if building a computer out of rubidium atoms and laser beams weren’t difficult enough, scientists sometimes have to work as if blindfolded: The quirks of quantum physics can cause correlations between the atoms to fade from view at crucial times.
Quantum Computer Demonstrated Quantum computing offers the potential to create value in areas where problems or requirements exceed the capability of digital computing, the company said. But D-Wave explains that its new device is intended as a complement to conventional computers, to augment existing machines and their market, not as a replacement for them.
Quantum Computing Breakthrough "Our work represents a breakthrough in the search for a nanoscopic [atomic scale] mechanism that could be used for a data readout device," says Christoph Boehme, assistant professor of physics at the University of Utah. "We have demonstrated experimentally that the nuclear spin orientation of phosphorus atoms embedded in silicon can be measured by very subtle electric currents passing through the phosphorus atoms."
Research: Ion Trap Physicists at the National Institute of Standards and Technology (NIST) have designed and built a novel electromagnetic trap for ions that could be easily mass produced to potentially make quantum computers large enough for practical use. The new trap, described in the June 30 issue of Physical Review Letters,* may help scientists surmount what is currently the most significant barrier to building a working quantum computer—scaling up components and processes that have been successfully demonstrated individually.
A Quantum Computer, One Dot at a Time Quantum computers do not yet exist, but it is known that they can bypass all known encryption schemes used today on the Internet. Quantum computers also are capable of efficiently solving the most important equation in quantum physics: the Schrödinger equation, which describes the time-dependence of quantum mechanical systems. Hence, if quantum computers can be built, they likely will have as large an impact on technology as the transistor.
Better Memory with Quantum Computer Bits Physicists at the National Institute of Standards and Technology (NIST) have used charged atoms (ions) to demonstrate a quantum physics version of computer memory lasting longer than 10 seconds—more than 100,000 times longer than in previous experiments on the same ions. The advance improves prospects for making practical, reliable quantum computers (which make use of the properties of quantum systems rather than transistors for performing calculations or storing information). Quantum computers, if they can be built, could break today’s best encryption systems, accelerate database searching, develop novel products such as fraud-proof digital signatures or simulate complex biological systems to help design new drugs.
