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arXiv · 2404.18091

Robust external spin hyperpolarization of quadrupolar nuclei enabled by strain

Lu Chen·Jiawen Jiang·Martin B. Plenio·Qiong Chen
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Abstract

In a theoretical study, we investigate the spin dynamics of interacting nitrogen-vacancy (NV) centers and quadrupolar I = 3/2 nuclear spins, specifically 11B spins in hexagonal boron nitride (h-BN) nanosheets located near the microdiamond surface. We demonstrate the possibility of obtaining external spin-polarization by magnetic-field sweeps across the level anticrossings around zero-field. To achieve this, we leverage crystal strains to establish a polarization transfer mechanism that remains robust against variations in NV orientation, crystal strain inhomogeneity, and electron-nuclear effective couplings. These results pave the way for hyperpolarization of spins in nanomaterials near the diamond surface without experiencing polarization loss to intrinsic nuclear spin-1/2 species, such as 13C and 1H nuclear spins in diamond. The 11B spins in h-BN nanosheets, with their extended relaxation time and large surface area, present a promising alternative for relayed nuclear polarization to the liquid phase and for the development of quantum simulators based on surface nuclear spins.

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Lu Chen, Jiawen Jiang, Martin B. Plenio, Qiong Chen. 2024-04-28. Robust external spin hyperpolarization of quadrupolar nuclei enabled by strain. https://doi.org/10.1103/physrevb.109.l180102

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