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arXiv · 2211.14943

Affinity-based geometric discord and quantum speed limits of its creation and decay

R. Muthuganesan·S. Balakrishnan
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Abstract

In this article, we define a faithful quantifiers of bipartite quantum correlation, namely geometric version of quantum discord using affinity based metric. It is shown that the newly-minted measure resolves the local ancilla problem of Hilbert-Schmidt measures. Exploiting the notion of affinity-based discord, we derive Margolus-Levitin (ML) and Mandelstamm-Tamm (MT) bounds for the quantum speed limit time for the creation and decay of quantum correlation. The dynamical study suggests that the affinity measure is a better resource compared to entanglement. Finally, we study the role of quantum correlation on quantum speed limit.

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R. Muthuganesan, S. Balakrishnan. 2022-11-27. Affinity-based geometric discord and quantum speed limits of its creation and decay. https://doi.org/10.1088/1402-4896%2Faca1ec

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