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arXiv:quant-ph/9904109 · Journal of Modern Optics

Explicit product ensembles for separable quantum states

Rüdiger Schack, Carlton M. Caves

Published Feb 1, 2000• 47 citations
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Abstract

We present a general method for constructing pure-product-state representations for density operators of N quantum bits. If such a representation has non-negative expansion coefficients, it provides an explicit separable ensemble for the density operator. We derive the condition for separability of a mixture of the Greenberger—Horne—Zeilinger state with the maximally mixed state.

DOI
10.1080/09500340008244050

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We present a general method for constructing pure-product-state representations for density operators of N quantum bits. If such a representation has non-negative expansion coefficients, it provides an explicit separable ensemble for the density operator. We derive the condition for separability of a mixture of the Greenberger—Horne—Zeilinger state with the maximally mixed state.
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