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Decoherence-free subspaces and subsystems for a collectively depolarizing bosonic channel

Jonathan L. Ball·Konrad Banaszek
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Abstract

We discuss the structure of decoherence-free subsystems for a bosonic channel affected by collective depolarization. A single use of the channel is defined as a transmission of a pair of bosonic modes. Collective depolarization consists in a random linear U(2) transformation of the respective mode operators, which is assumed to be identical for $N$ consecutive uses of the channel. We derive a recursion formula that characterizes the dimensionality of available decoherence-free subsystems in such a setting.

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Jonathan L. Ball, Konrad Banaszek. 2005-06-02. Decoherence-free subspaces and subsystems for a collectively depolarizing bosonic channel. https://doi.org/10.1007/s11080-005-5723-1

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