Bound entanglement can maximally violate Bell inequalities

Remigiusz Augusiak, Paweł Horodecki

Published May 30, 2004• 0 citations

Abstract

It is shown that some four-qubit bound entangled states can maximally violate two-setting Bell inequality similar to standard CHSH inequality. Surprisingly this entanglement does not allow for secure key distillation, so neither entanglement nor violation of Bell inequalities implies quantum security. It is also pointed out how that kind of bound entanglement can be useful in reducing communication complexity.

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