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arXiv · 1109.0954

Fundamental Speed Limits on Quantum Coherence and Correlation Decay

Daniel Oi·Sophie Schirmer
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Abstract

The study and control of coherence in quantum systems is one of the most exciting recent developments in physics. Quantum coherence plays a crucial role in emerging quantum technologies as well as fundamental experiments. A major obstacle to the utilization of quantum effects is decoherence, primarily in the form of dephasing that destroys quantum coherence, and leads to effective classical behaviour. We show that there are universal relationships governing dephasing, which constrain the relative rates at which quantum correlations can disappear. These effectively lead to speed limits which become especially important in multi-partite systems.

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Daniel Oi, Sophie Schirmer. 2011-09-05. Fundamental Speed Limits on Quantum Coherence and Correlation Decay. https://doi.org/10.1103/physreva.86.012121

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