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arXiv · 2401.16902

One-excitation spin dynamics in homogeneous closed chain governed by XX-Hamiltonian

E. B. Fel'dman·E. I. Kuznetsova·A. I. Zenchuk
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Abstract

We analytically investigate the one-excitation spin dynamics in a homogeneous closed spin-1/2 chain via diagonalization of the one-excitation block of the XX-Hamiltonian, which allows to derive the analytical expressions for probability amplitudes describing state transfers between any two spins of a chain. We analytically investigate the $M$-neighbor approximation ($M\ge 1$) of spin dynamics with arbitrary initial state and analyze its accuracy using special integral characteristics defined in terms of the above probability amplitudes. We find $M$ providing the required accuracy of evolution approximation for chains of different lengths.

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E. B. Fel'dman, E. I. Kuznetsova, A. I. Zenchuk. 2024-01-30. One-excitation spin dynamics in homogeneous closed chain governed by XX-Hamiltonian. https://doi.org/10.1007/s11128-023-04250-4

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