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arXiv · 1503.08617

Protected quantum-state transfer in decoherence-free subspaces

Wei Qin·Chuan Wang·Xiangdong Zhang
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Abstract

We propose and analyse a robust quantum state transfer protocol by the use of a combination of coherent quantum coupling and decoherence-free subspaces in a coupled quantum spin chain. Under decoherence, an arbitrary unknown quantum state embedded in a decoherence-free subspace can be perfectly transferred through a noisy channel being weakly coupled to two end registers. The method protects quantum information from both the channel noise and the environmental decoherence. A special case of utilizing two physical qubits to encode one logical qubit is considered as an example and the robustness is confirmed by numerical performances.

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Wei Qin, Chuan Wang, Xiangdong Zhang. 2015-04-07. Protected quantum-state transfer in decoherence-free subspaces. https://doi.org/10.1103/physreva.91.042303

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