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arXiv · 2112.05223

Electronic control and switching of entangled spin state using anisotropy and exchange in the three-particle paradigm

Eric D. Switzer·Xiao-Guang Zhang·Talat S. Rahman
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Abstract

We explore the control and switching of the entangled spin states of multi-spin particle qubit coupled to an electron using a three-particle spin model described by $S_i$ ($i=1,2,3$), in which $S_1=\tfrac{1}{2}$ is an electron and $S_{2,3}$ can have any spin with both exchange coupling and magnetic anisotropy. We derive a general formula for the existence of a switching (DJ) resonance for any spin $S_{2,3}$. We further contrast the entanglement switching mechanisms for the $S_{2,3}=\tfrac{1}{2}$ and $S_{2,3}=1$ spin models. We find that while the onsite magnetic anisotropy in the case of $S_{2,3}>\tfrac{1}{2}$ allows full control of their spin states via interaction with $S_1$, in order to achieve acceptable control of a Bloch vector within the $S_{2,3}=\tfrac{1}{2}$ model, additional mechanisms, such as anisotropic exchange coupling, are required.

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Eric D. Switzer, Xiao-Guang Zhang, Talat S. Rahman. 2021-12-09. Electronic control and switching of entangled spin state using anisotropy and exchange in the three-particle paradigm. https://doi.org/10.1088/2399-6528%2Fac7e1d

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