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Depolarization channels with zero-bandwidth noises

Andrzej Dragan·Krzysztow Wódkiewicz
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Abstract

A simple model describing depolarization channels with zero-bandwidth environment is presented and exactly solved. The environment is modelled by Lorentzian, telegraphic and Gaussian zero-bandwidth noises. Such channels can go beyond the standard Markov dynamics and therefore can illustrate the influence of memory effects of the noisy communication channel on the transmitted information. To quantify the disturbance of quantum states the entanglement fidelity between arbitrary input and output states is investigated.

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Andrzej Dragan, Krzysztow Wódkiewicz. 2004-07-21. Depolarization channels with zero-bandwidth noises. https://doi.org/10.1103/physreva.71.012322

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