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arXiv · 1411.0271

The Roles of a Quantum Channel on a Quantum State

Lin Wang·Chang-shui Yu
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Abstract

When a quantum state undergoes a quantum channel, the state will be inevitably influenced. In general, the fidelity of the state is reduced, so is the entanglement if the sub- systems go through the channel. However, the influence on the coherence of the state is quite different. Here we present some state-independent quantities to describe to what degree the fidelity, the entanglement and the coherence of the state are influenced. As applications, we consider some quantum channels on a qubit and find that the infidelity ability monotonically depends on the decay rate, but in usual the decoherence ability is not the case and strongly depends on the channel.

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Lin Wang, Chang-shui Yu. 2014-11-02. The Roles of a Quantum Channel on a Quantum State. https://arxiv.org/abs/1411.0271

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