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arXiv · 0705.1398

Experimental demonstration of Shor's algorithm with quantum entanglement

B. P. Lanyon·T. J. Weinhold·N. K. Langford·M. Barbieri·D. F. V. James*·A. Gilchrist·A. G. White
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Abstract

Shor's powerful quantum algorithm for factoring represents a major challenge in quantum computation and its full realization will have a large impact on modern cryptography. Here we implement a compiled version of Shor's algorithm in a photonic system using single photons and employing the non-linearity induced by measurement. For the first time we demonstrate the core processes, coherent control, and resultant entangled states that are required in a full-scale implementation of Shor's algorithm. Demonstration of these processes is a necessary step on the path towards a full implementation of Shor's algorithm and scalable quantum computing. Our results highlight that the performance of a quantum algorithm is not the same as performance of the underlying quantum circuit, and stress the importance of developing techniques for characterising quantum algorithms.

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B. P. Lanyon, T. J. Weinhold, N. K. Langford, M. Barbieri, D. F. V. James*, A. Gilchrist, A. G. White. 2007-10-16. Experimental demonstration of Shor's algorithm with quantum entanglement. https://doi.org/10.1103/physrevlett.99.250505

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