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arXiv · 1010.0472

Efficient tomography of quantum processes

Xiang-Bin Wang·J. -Z. Hu·Z. -W. Yu·Franco Nori
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Abstract

We show with explicit formulas that one can completely identify an unknown quantum process with only one weakly entangled state; and identify a quantum optical Gaussian process with either one two-mode squeezed state or a few different coherent states. In tomography of a multi-mode process, our method reduces the number of different test states exponentially compared with existing methods.

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Xiang-Bin Wang, J. -Z. Hu, Z. -W. Yu, Franco Nori. 2010-10-04. Efficient tomography of quantum processes. https://arxiv.org/abs/1010.0472

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