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arXiv · 2504.15832

Restoring of quantum state transferred along XY-spin chain and entanglement evolution

N. A. Tashkeev·A. I. Zenchuk
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Abstract

We propose a protocol restoring the state transferred along the spin chain governed by the XY-Hamiltonian. Such dynamics does not preserve the excitation number and leads to mixing multiple-quantum coherence matrices of orders having the same parities. Depending on the initial state, this results in generating ether all possible or only even-order multiple-quantum coherence matrices. Restoring is established via the special unitary transformation applied to the receiver side of the chain (extended receiver). An example of restoring $\pm1$ and $\pm 2$-order coherence matrices in two-qubit state transfer is considered. Entanglement transfer in such process is also studied and possibility of its amplification is demonstrated.

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N. A. Tashkeev, A. I. Zenchuk. 2025-04-22. Restoring of quantum state transferred along XY-spin chain and entanglement evolution. https://arxiv.org/abs/2504.15832

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