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arXiv · 1311.4692

Protecting qutrit-qutrit entanglement by weak measurement and reversal

Xing Xiao·Yan-Ling Li
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Abstract

Entangled states in high dimensional systems are of great interest due to the extended possibilities they provide in quantum information processing. Recently, Sun et al. [Phys. Rev. A 82, 052323 (2010)] and Kim et al. [Nat. Phys. 8, 117 (2012)] pointed out that weak measurement and quantum weak measurement reversal can actively combat decoherence. We generalize their studies from qubits to qutrits under amplitude damping decoherence. We find that the qutrit-qutrit entanglement can be partially retrieved for certain initial states when only weak measurement reversals are performed. However, we can completely defeat amplitude damping decoherence for any initial states by the combination of prior weak measurements and post optimal weak measurement reversals. The experimental feasibility of our schemes is also discussed.

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Xing Xiao, Yan-Ling Li. 2017-06-30. Protecting qutrit-qutrit entanglement by weak measurement and reversal. https://doi.org/10.1140/epjd%2Fe2013-40036-3

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