arXiv:1312.3332 · New Journal of Physics

How discord underlies the noise resilience of quantum illumination

Christian Weedbrook, Stefano Pirandola, Jayne E. Thompson, Vlatko Vedral, Mile Gu

Published Apr 18, 2016• 83 citations

Abstract

The benefits of entanglement can outlast entanglement itself. In quantum illumination, entanglement is employed to better detect reflecting objects in environments so noisy that all entanglement is destroyed. Here, we show that quantum discord—a more resilient form of quantum correlations—explains the resilience of quantum illumination. We introduce a quantitative relation between the performance gain in quantum illumination and the amount of discord used to encode information about the presence or absence of a reflecting object. This highlights discords role preserving the benefits of entanglement in entanglement breaking noise.

DOI: 10.1088/1367-2630/18/4/043027

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