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arXiv · 2205.03808

Ground-state and dynamical properties of a spin-$S$ Heisenberg star

Jiaxiu Li·Ning Wu
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Abstract

We generalize the Heisenberg star consisting of a spin-1/2 central spin and a homogeneously coupled spin bath modeled by the XXX ring [Richter J and Voigt A 1994 \emph{J. Phys. A: Math. Gen.} \textbf{27} 1139-1149] to the case of arbitrary central-spin size $S 1/2$ exhibits collapse-revival behaviors with fine structures. However, the collapse-revival phenomena is found to be fragile with respect to anisotropy of the intrabath coupling.

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Jiaxiu Li, Ning Wu. 2022-05-08. Ground-state and dynamical properties of a spin-$S$ Heisenberg star. https://doi.org/10.1088/1572-9494%2Fac7b17

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