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arXiv · 2302.10192

Tridiagonal Toeplitz Matrices and Bipartite Quantum Correlations

Varsha S. Sambhaje·Suprabhat Sinha·Kapil K. Sharma
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Abstract

In this article, we focus on tridiagonal Toeplitz Hermitian matrices, which fulfill the requirement of a valid Hamiltonian often used in Quantum Information. We investigate the behavior of such matrices to pursue the dynamics of quantum correlations (entanglement and quantum discord) for bipartite Werner state and maximally entangled mixed states. We have found interesting results that the main diagonal terms in the Toeplitz matrices never affect the quantum correlations in both quantum states. However, super-diagonal and sub-diagonal terms play the important role in the dynamics. We investigate the phenomenon of entanglement sudden death and also observe the presence of quantum discord in the absence of entanglement. Most importantly it is found that MEMS is more sensitive in comparison to the Werner state.

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Varsha S. Sambhaje, Suprabhat Sinha, Kapil K. Sharma. 2023-04-29. Tridiagonal Toeplitz Matrices and Bipartite Quantum Correlations. https://arxiv.org/abs/2302.10192

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