For the last fifty years computers have grown faster, smaller, and more powerful, transforming and benefiting our society in ways too much to count. But like any exponential explosion of resources, this growth known as Moore's law must soon come to an end. Research has already begun on what comes after our current computing revolution. This research has discovered the possibility for an entirely new type of computer, one that operates according to the laws of quantum physics, a quantum computer.
A quantum computer would not just be a traditional computer built out of different parts, but a machine that would exploit the laws of quantum physics to perform certain information processing tasks in a better and more efficient manner. One demonstration of this potential is that quantum computers would break the codes that protect our modern computing infrastructure the security of every Internet transaction would be broken if a quantum computer were to be built. This potential has made quantum computing a national security concern. Yet at the same time, quantum computers will also revolutionize large parts of science in a more benevolent way. Simulating large quantum systems, something a quantum computer can easily do, is not practically possible on a traditional computer.
A technology of quantum computers is also very different. For operation, quantum computer uses quantum bits (qubits). Qubit has a quaternary nature. Quantum mechanic’s laws are completely different from the laws of a classical physics. A qubit can exist not only in the states corresponding to the logical values 0 or 1 as in the case of a classical bit, but also in a superposition state.
A qubit is a bit of information that can be both zero and one simultaneously (Superposition state). Thus, a computer working on a qubit rather than a standard bit can make calculations using both values simultaneously. A qubyte is made up of eight qubits and can have all values from zero to 255 simultaneously. “Multi-qubyte systems have a power beyond anything possible with classical computers.” (Quantum Computers & Moore's Law, p.1)
From detailed simulations of biological molecules which will advance the health sciences, to aiding research into novel materials for harvesting electricity from light, a quantum computer will likely be an essential tool for future progress in chemistry, physics, and engineering. Finally, quantum computers represent a fundamentally new way of approaching information processing and, because this approach is based more closely on how our universe operates, it is likely that building a quantum computer will lead to unforeseen technologies and transform our understanding of the possibilities and limits of computation. For these reasons, as well as increasing international competition in the area, a major national investment should be undertaken in quantum computing and information as part of the new Administration’s science and technology agenda.
Massachusetts Institute of Technology, Oxford University, IBM and Los Alamos National Laboratory are the most successful in development of quantum computer.