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arXiv · 2206.14771

The role of electron polarization on nuclear spin diffusion

Alessandro Chessari·Samuel F. Cousin·Sami Jannin·Quentin Stern
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Abstract

Dynamic nuclear polarization (DNP) is capable of boosting signals in nuclear magnetic resonance by orders of magnitude by creating out-of-equilibrium nuclear spin polarization. The diffusion of nuclear spin polarization in the vicinity of paramagnetic dopants is a crucial step for DNP and remains yet not well understood. In this Letter, we show that the polarization of the electron spin controls the rate of proton spin diffusion in a DNP sample at 1.2 K and 7 T; at increasingly high electron polarization, spin diffusion vanishes. We rationalize our results using a 2 nucleus - 1 electron model and Lindblad s Master equation, which generalizes preexisting models in the literature and qualitatively accounts for the experimental observed spin diffusion dynamics.

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Alessandro Chessari, Samuel F. Cousin, Sami Jannin, Quentin Stern. 2022-06-29. The role of electron polarization on nuclear spin diffusion. https://doi.org/10.1103/physrevb.107.224429

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