A scheme for a random number generator based on the intrinsic randomness of quantum mechanics is proposed. A Fresnel multiple prism which can act as a perfect 50∕50 beam splitter is used to realize the random events by choosing single photons from a polarized laser beam. A procedure to get rid of the bias of the raw sequences is discussed in detail together with the random number generation efficiency per light pulse.

A generalized quantum search algorithm, where phase inversions for the marked state and the prepared state are replaced by π/2 phase rotations, is realized in a 2-qubit NMR heteronuclear system. The quantum algorithm searches a marked state with a smaller step compared to standard Grover algorithm. Phase matching requirement in quantum searching is demonstrated by comparing it with another generalized algorithm where the two phase rotations are π/2 and 3π/2 respectively. Pulse sequences which include non 90 1

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