Elementary gates for quantum computation

We show that a set of gates that consists of all one-bit quantum gates [U(2)] and the two-bit exclusive-OR gate [that maps Boolean values (x,y) to (x,x\ensuremath{\bigoplus}y)] is universal in the sense that all unitary operations on arbitrarily many bits n [U(${2}^{\mathit{n}}$)] can be expressed a... View More