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arXiv · 2406.11953

Intrinsic high-fidelity spin polarization of charged vacancies in hexagonal boron nitride

Wonjae Lee·Vincent S. Liu·Zhelun Zhang·Sangha Kim·Ruotian Gong·Xinyi Du·Khanh Pham·Thomas Poirier·Zeyu Hao·James H. Edgar·Philip Kim·Chong Zu·Emily J. Davis·Norman Y. Yao
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Abstract

The negatively charged boron vacancy ($\mathrm{V}_{\mathrm{B}}^-$) in hexagonal boron nitride (hBN) has garnered significant attention among defects in two-dimensional materials. This owes, in part, to its deterministic generation, well-characterized atomic structure, and optical polarizability at room temperature. We investigate the latter through extensive measurements probing both the ground and excited state polarization dynamics. We develop a semiclassical model based on these measurements that predicts a near-unity degree of spin polarization, surpassing other solid-state spin defects under ambient conditions. Building upon our model, we include the presence of nuclear spin degrees of freedom adjacent to the $\mathrm{V}_{\mathrm{B}}^-$ and perform a comprehensive set of Lindbladian numerics to investigate the hyperfine-induced polarization of the nuclear spins. Our simulations predict a number of important features that emerge as a function of magnetic field which are borne out by experiment.

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Wonjae Lee, Vincent S. Liu, Zhelun Zhang, Sangha Kim, Ruotian Gong, Xinyi Du, Khanh Pham, Thomas Poirier, Zeyu Hao, James H. Edgar, Philip Kim, Chong Zu, Emily J. Davis, Norman Y. Yao. 2024-06-17. Intrinsic high-fidelity spin polarization of charged vacancies in hexagonal boron nitride. https://doi.org/10.1103/physrevlett.134.096202

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