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arXiv · 1002.3064

Entanglement dynamics of three-qubit states in noisy channels

Michael Siomau·Stephan Fritzsche
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Abstract

We study entanglement dynamics of the three-qubit system which is initially prepared in pure Greenberger-Horne- Zeilinger (GHZ) or W state and transmitted through one of the Pauli channels $σ_z, \, σ_x, \, σ_y$ or the depolarizing channel. With the help of the lower bound for three-qubit concurrence we show that the W state preserves more entanglement than the GHZ state in transmission through the Pauli channel $σ_z$. For the Pauli channels $σ_x, \, σ_y$ and the depolarizing channel, however, the entanglement of the GHZ state is more resistant against decoherence than the W-type entanglement. We also briefly discuss how the accuracy of the lower bound approximation depends on the rank of the density matrix under consideration.

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Michael Siomau, Stephan Fritzsche. 2010-04-11. Entanglement dynamics of three-qubit states in noisy channels. https://doi.org/10.1140/epjd%2Fe2010-00189-1

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