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arXiv · 1006.4764

Quantum walks of correlated particles

Alberto Peruzzo·Mirko Lobino·Jonathan C. F. Matthews·Nobuyuki Matsuda·Alberto Politi·Konstantinos Poulios·Xiao-Qi Zhou·Yoav Lahini·Nur Ismail·Kerstin Wörhoff·Yaron Bromberg·Yaron Silberberg·Mark G. Thompson·Jeremy L. O'Brien
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Abstract

Quantum walks of correlated particles offer the possibility to study large-scale quantum interference, simulate biological, chemical and physical systems, and a route to universal quantum computation. Here we demonstrate quantum walks of two identical photons in an array of 21 continuously evanescently-coupled waveguides in a SiOxNy chip. We observe quantum correlations, violating a classical limit by 76 standard deviations, and find that they depend critically on the input state of the quantum walk. These results open the way to a powerful approach to quantum walks using correlated particles to encode information in an exponentially larger state space.

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Alberto Peruzzo, Mirko Lobino, Jonathan C. F. Matthews, Nobuyuki Matsuda, Alberto Politi, Konstantinos Poulios, Xiao-Qi Zhou, Yoav Lahini, Nur Ismail, Kerstin Wörhoff, Yaron Bromberg, Yaron Silberberg, Mark G. Thompson, Jeremy L. O'Brien. 2010-06-24. Quantum walks of correlated particles. https://doi.org/10.1126/science.1193515

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