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All (qubit) decoherences: Complete characterization and physical implementation

Mario Ziman·Vladimir Buzek
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Abstract

We investigate decoherence channels that are modelled as a sequence of collisions of a quantum system (e.g., a qubit) with particles (e.g., qubits) of the environment. We show that collisions induce decoherence when a bi-partite interaction between the system qubit and an environment (reservoir) qubit is described by the controlled-U unitary transformation (gate). We characterize decoherence channels and in the case of a qubit we specify the most general decoherence channel and derive a corresponding master equation. Finally, we analyze entanglement that is generated during the process of decoherence between the system and its environment.

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Mario Ziman, Vladimir Buzek. 2005-05-10. All (qubit) decoherences: Complete characterization and physical implementation. https://doi.org/10.1103/physreva.72.022110

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