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arXiv · 1710.04601

Certifying an irreducible 1024-dimensional photonic state using refined dimension witnesses

Edgar A. Aguilar·Máté Farkas·Daniel Martínez·Matías Alvarado·Jaime Cariñe·Guilherme B. Xavier·Johanna F. Barra·Gustavo Cañas·Marcin Pawłowski·Gustavo Lima
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Abstract

We report on a new class of dimension witnesses, based on quantum random access codes, which are a function of the recorded statistics and that have different bounds for all possible decompositions of a high-dimensional physical system. Thus, it certifies the dimension of the system and has the new distinct feature of identifying whether the high-dimensional system is decomposable in terms of lower dimensional subsystems. To demonstrate the practicability of this technique we used it to experimentally certify the generation of an irreducible 1024-dimensional photonic quantum state. Therefore, certifying that the state is not multipartite or encoded using non-coupled different degrees of freedom of a single photon. Our protocol should find applications in a broad class of modern quantum information experiments addressing the generation of high-dimensional quantum systems, where quantum tomography may become intractable.

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Edgar A. Aguilar, Máté Farkas, Daniel Martínez, Matías Alvarado, Jaime Cariñe, Guilherme B. Xavier, Johanna F. Barra, Gustavo Cañas, Marcin Pawłowski, Gustavo Lima. 2017-10-12. Certifying an irreducible 1024-dimensional photonic state using refined dimension witnesses. https://doi.org/10.1103/physrevlett.120.230503

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