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arXiv · 2112.14805

Theory of spin-polarized current flow through a localized spin triplet state

Stephen R. McMillan·Michael E. Flatté
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Abstract

We derive a formalism describing quantum-coherent features of spin-polarized charge current through a partially-polarized spin triplet defect in a $\textit{transverse}$ magnetic field. We predict distinct few-milli-tesla-dc magnetoresistance signatures that identify a $\textit{single}$ spin-triplet center's character and reveal the orientation of the spin triplet's zero-field splitting axis relative to the magnetic contact's polarization. For example, in 4H-SiC the single $(hh)$, $(kk)$, $(hk)$, and $(kh)$ divacancies are all distinct. Spin-polarized current flow efficiently polarizes the spin, potentially electrically initializing spin-triplet-based qubits.

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Stephen R. McMillan, Michael E. Flatté. 2021-12-29. Theory of spin-polarized current flow through a localized spin triplet state. https://arxiv.org/abs/2112.14805

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