Basic Ideas of Quantum Computation

Information is always stored and used by physical means. Modern computers rely on properties of semiconductors to achieve computation, the explanation of which belongs completely to quantum mechanics. We can infer then that every present computer is a quantum computer –but they do not come near quantum computation; they do not exploit their “quantumness ” The idea of quantum computation originates from the early works of Feyman and Deutsch in the early 1980’s. The power of quantum computation rests on the full use of quantum phenomena, thus we are not only taking into account but using the (theoretical –yet!) computer’s “quantumness”. What this scientists realized was that while a classical computer takes a timewise exponential path to find the solution of s me problems, a quantum computer gives the solution in linear time. To understand what can be achieved,, we first need to formalize the basic concepts underlying quantum computation