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Making Noisy Quantum Channels Transparent

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 Publication date 2021
  fields Physics
and research's language is English




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One of the major obstacles faced by quantum-enabled technology is the environmental noise that causes decoherence in the quantum system, thereby destroying much of its quantum aspects and introduces errors while the system undergoes quantum operations and processing. A number of techniques have been invented to mitigate the environmental effects; however, much of these techniques are specific to the environment and the quantum tasks at hand, limiting their applicability. Here we propose a protocol that makes arbitrary environments effectively noise-free or transparent. The protocol exploits non-local superposition in evolution as a quantum resource. Consequently, it enables full protection of quantum information and entanglement from decoherence, and perfect quantum communications across arbitrary noisy channels for any finite-dimensional quantum system. We also propose experimental schemes to implement this protocol on linear optical and atomic systems.

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