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arXiv · 1210.5645

A statistical portrait of the entanglement decay of two-qubit memories

Karen M. Fonseca-Romero·Julián Martínez-Rincón·Carlos Viviescas
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Abstract

We present a novel approach to the study of entanglement decay, which focuses on collective properties. As an example, we investigate the entanglement decay of a two-qubit system, produced by local identical reservoirs acting on the qubits, for three experimentally and theoretically relevant cases. We study the probability distributions of disentanglement times, a quantity independent of the measure used to quantify entanglement, and the time-dependent probability distribution of concurrence. Analytical results are obtained for initially uniformly distributed pure states. The calculation of these probability distributions gives a complete insight on how different decoherence channels affect the entanglement initially contained in the set of two-qubit pure states. Numerical results are reported for randomly distributed initial mixed states. Although the paper focuses in Markovian noisy channels, we show that our results also describe non-autonomous and non-Markovian channels.

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Karen M. Fonseca-Romero, Julián Martínez-Rincón, Carlos Viviescas. 2012-10-20. A statistical portrait of the entanglement decay of two-qubit memories. https://doi.org/10.1103/physreva.86.042325

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