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arXiv · 2502.21010

Analytic Formulas for Quantum Discord of Special Families of N-Qubit States

Jianming Zhou·Xiaoli Hu·Honglian Zhang·Naihuan Jing
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Abstract

Quantum discord, a key indicator of non-classical correlations in bipartite systems, has been recently extended to multipartite scenarios [Phys. Rev. Lett. 2020, 124:110401]. We present exact analytic formulas for the quantum discord of special families of N-qubit states, including generalized class of GHZ states. Our formulations span $2$, $3$, $4n$, $4n+1$, $4n+2$, and $4n+3$-qubit configurations where $n\in 1, 2, \ldots$, which refine the assessment of quantum correlations and provide an analytical tool in quantum computation. Moreover, we uncover a ``discord freezing'' in even-qubit systems under phase flip decoherence which provides a means for preserving quantum coherence in environmental perturbations.

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Jianming Zhou, Xiaoli Hu, Honglian Zhang, Naihuan Jing. 2025-02-28. Analytic Formulas for Quantum Discord of Special Families of N-Qubit States. https://doi.org/10.1007/s11128-024-04625-1

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