An error-free protocol for quantum entanglement distribution in long-distance quantum communication

Chinese Science Bulletin (Impact Factor: 1.37). 01/2010; 56(7):618-625. DOI: 10.1007/s11434-010-4336-4
Source: DBLP

ABSTRACT Quantum entanglement distribution is an essential part of quantum communication and computation protocols. Here, linear optic
elements are employed for the distribution of quantum entanglement over a long distance. Polarization beam splitters and wave
plates are used to realize an error-free protocol for broadcasting quantum entanglement in optical quantum communication.
This protocol can determine the maximum distance of quantum communication without decoherence. Error detection and error correction
are performed in the proposed scheme. In other words, if there is a bit flip along the quantum channel, the end stations (Alice
and Bob) can detect this state change and obtain the correct state (entangled photon) at another port. Existing general error
detection protocols are based on the quantum controlled-NOT (CNOT) or similar quantum logic operations, which are very difficult
to implement experimentally. Here we present a feasible scheme for the implementation of entanglement distribution based on
a linear optics element that does not need a quantum CNOT gate.

Keywordsquantum entanglement–quantum communication–quantum error detection–decoherence–error correction

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