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arXiv · 1004.2297

Fast entanglement detection for unknown states of two spatial qutrits

G. Lima·E. S. Gómez·A. Vargas·R. O. Vianna·C. Saavedra
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Abstract

We investigate the practicality of the method proposed by Maciel et al. [Phys. Rev. A. 80, 032325(2009)] for detecting the entanglement of two spatial qutrits (3-dimensional quantum systems), which are encoded in the discrete transverse momentum of single photons transmitted through a multi-slit aperture. The method is based on the acquisition of partial information of the quantum state through projective measurements, and a data processing analysis done with semi-definite programs. This analysis relies on generating gradually an optimal entanglement witness operator, and numerical investigations have shown that it allows for the entanglement detection of unknown states with a cost much lower than full state tomography.

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G. Lima, E. S. Gómez, A. Vargas, R. O. Vianna, C. Saavedra. 2010-04-14. Fast entanglement detection for unknown states of two spatial qutrits. https://doi.org/10.1103/physreva.82.012302

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