Experimental NMR Realization of A Generalized Quantum Search Algorithm
G. L. Long, H. Y. Yan, Y. S. Li, C. C. Tu, J. X. Tao, H. M. Chen, M. L. Liu, Xue Zhang, J. L. Luo, Xiao Li, X. Z. Zeng · 2008
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 degree pulses are given. Typeset using REVTEX 2 Grover’s quantum search algorithm is one of the most important development in quantum computation [1]. It achieves quadratic speedup in searching a marked state in an unordered list over classical searching algorithms. It has many potential applications in various fields of interests, for instance in deciphering the DES encryption code [2] and algorithms that need searching. Typical examples of the algorithms that need searching are the Simon