In this article, we investigate how quantum correlations behave for the so-called Werner and pseudopure families of states. The latter refers to states formed by mixing any pure state with the totally mixed state. We derive closed expressions for the quantum discord and the relative entropy of quantumness for these families of states. For Werner states, the classical correlations are seen to vanish in high dimensions while the amount of quantum correlations remains bounded. For pseudopure states, nearly the opposite effect is observed, with both the quantum and classical correlations growing without bound as the dimension increases and only as the system becomes more entangled. In light of our calculations, we discuss how Werner states could play a role as a quantum one-time pad in cryptographic tasks and, along with isotropic states, could function as a quantum memory device designed to maximize the uncertainty tradeoff between noncommuting measurements on the individual subsystems.
|Original language||English (US)|
|Journal||Physical Review A - Atomic, Molecular, and Optical Physics|
|State||Published - Sep 12 2012|
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics