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According to PhysicsWorld researchers from the University of Sao Paulo, Brazil and Max Planck Institute for the Science of Light, Erlangen, Germany have added another capability to the quantum computing toolkit by being the first to show that light beams of three different wavelengths can be entangled. This achievement could provide a way to create three-way optical communication links between elements of a quantum computer. This result was published in the recent issue of Science magazine.

Quantum cryptography is a promising new way to send encrypted information. This new technology does suffer from some drawbacks. One of the toughest problems is the range that information can be sent is limited to around 50-100 km. Advancements have been underway. The most promising advancement is being working on by a team based out of the Australian National University. They found a way to store and manipulate photons to be used as a memory device.

<p>According to Physics World researchers at the University of Bristol, UK have made a prototype optical quantum computer chip and used it to perform a mathematical calculation. The device consists of tiny silica waveguides on a silicon chip and carries out a version of the quantum calculation known as Shor's algorithm. The result is an important step towards making practical, real-world quantum computers.</p>
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New results in quantum cryptography show that the original protocol based on Bell's inequality is so powerful that it extends beyond the quantum realm. In the recent issue of Physics World Artur Ekert traces it all back to Einstein's considerations about physical reality.

Researchers in Austria, Germany and the US, proposed a scheme to couple the motion of a single atom with a crystal membrane. This scheme could be used to observe quantum-mechanical effects on a larger scale than ever before.

Researchers at the National Institute of Standards and Technology (NIST) in Boulder, CO, have demonstrated multiple computing operations on quantum bits--a crucial step toward building a practical quantum computer.

Precise control of quantum effects is vital to the realization of entirely new technologies. For example, a computer based on quantum physical principles is expected to outperform today's classical computers. In communication technology, quantum devices are already commercially available which allow secure transmission of data. Controlling the properties of photons down to the quantum level is at the heart of these technologies. In recent years, scientists in the group of Prof.

Single atoms have been spotted doing the quantum version of the random walk by physicists in Germany. This sighting of a “quantum walk” could help in the design of quantum search algorithms, or in the understanding of the transition from the quantum, microscopic world to the classical, macroscopic world.

The QI group at the University of Leeds is launching a new taught MSc programme in Quantum Technologies this year.

Quantum Information Theory is the study of information-processing tasks such as storage and transmission of information, or manipulation of entanglement, using quantum-mechanical systems. Until very recently, the study of these processes was limited to the case in which the required resources, e.g. information sources, communication channels or entanglement resources, were assumed to be available for an infinite number of independent uses.