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Factoring the unitary evolution operator and quantifying entanglement

X. X. Yi·C. P. Sun
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Abstract

The unitary evolution can be represented by a finite product of exponential operators. It leads to a perturbative expression of the density operator of a close system. Based on the perturbative expression scheme, we present a entanglement measure, this measure has the advantage that it is easy to compute for a general dynamical process.

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X. X. Yi, C. P. Sun. 2000-03-07. Factoring the unitary evolution operator and quantifying entanglement. https://doi.org/10.1016/s0375-9601(99)00609-x

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