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arXiv · 1203.3331

Quantum-memory-assisted entropic uncertainty principle under noise

Z. Y. Xu·W. L. Yang·M. Feng
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Abstract

The measurement outcomes of two incompatible observables on a particle can be precisely predicted when it is maximally entangled with a quantum memory, as quantified recently [Nature Phys. 6, 659 (2010)]. We explore the behavior of the uncertainty relation under the influence of local unital and nonunital noisy channels. While the unital noises only increase the amount of uncertainty, the amplitude-damping nonunital noises may amazingly reduce the amount of uncertainty in the long-time limit. This counterintuitive phenomenon could be justified by different competitive mechanisms between quantum correlations and the minimal missing information after local measurement.

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Z. Y. Xu, W. L. Yang, M. Feng. 2012-03-15. Quantum-memory-assisted entropic uncertainty principle under noise. https://doi.org/10.1103/physreva.86.012113

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