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arXiv · 2210.17248

Intrinsic decoherence effects on correlated coherence and quantum discord in XXZ Heisenberg model

Zakaria Dahbi·Mansoura Oumennana·Mostafa Mansour
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Abstract

Spin qubits are at the heart of technological advances in quantum processors and offer an excellent framework for quantum information processing. This work characterizes the time evolution of coherence and nonclassical correlations in a two-spin XXZ Heisenberg model, from which a two-qubit system is realized. We study the effects of intrinsic decoherence on coherence (correlated coherence) and nonclassical correlations (quantum discord), taking into consideration the combined impact of an external magnetic field, Dzyaloshinsky-Moriya (DM) and Kaplan Shekhtman Entin-Wohlman-Aharony (KSEA) interactions. To fully understand the effects of intrinsic decoherence, we suppose that the system can be prepared in one of the two well-known extended Werner-like (EWL) states. The findings show that intrinsic decoherence leads the coherence and quantum correlations to decay and that the behavior of the aforementioned quantum resources relies strongly on the initial EWL state parameters. We, likewise, found that the two-spin correlated coherence and quantum discord; become more robust against intrinsic decoherence depending on the type of the initial state. These outcomes shed light on how a quantum system should be engineered to achieve quantum advantages.

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Zakaria Dahbi, Mansoura Oumennana, Mostafa Mansour. 2022-11-09. Intrinsic decoherence effects on correlated coherence and quantum discord in XXZ Heisenberg model. https://doi.org/10.1007/s11082-023-04604-3

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