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arXiv · 1509.05307

Non-Markovian dynamics in two-qubit dephasing channels with an application to superdense coding

Antti Karlsson·Henri Lyyra·Elsi-Mari Laine·Sabrina Maniscalco·Jyrki Piilo
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Abstract

We study the performance of two measures of non-Markovianity in detecting memory effects in two-qubit dephasing channels. By combining independent Markovian and non-Markovian noise on the qubits, our results show that the trace distance measure is able to detect the memory effects when at least one of the local channels displays non-Markovianity. A measure based on channel capacity, in turn, becomes non-zero when the global two-qubit dynamics shows memory effects. We apply these schemes to a well-known superdense coding protocol and demonstrate an optimal noise configuration to maximize the information transmission with independent local noises.

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Antti Karlsson, Henri Lyyra, Elsi-Mari Laine, Sabrina Maniscalco, Jyrki Piilo. 2015-09-17. Non-Markovian dynamics in two-qubit dephasing channels with an application to superdense coding. https://doi.org/10.1103/physreva.93.032135

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