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arXiv · 2506.21916

First-order nuclear dipolar order in rotating solids

Kohei Suzuki·Kazuyuki Takeda
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Abstract

Nuclear spins' dipolar order is created under magic angle spinning through the first-order process made possible by simultaneous implementation of dipolar recoupling and adiabatic demagnetization in a reference frame reached out through nested transformations, firstly from the laboratory frame into the rotating frame, and then into the spin coordinate system nutating inside its parent frame. In such a nutating frame, both the static and resonantly rotating radio-frequency (RF) fields are invisible, and the re-introduced dipolar interaction provides a secular eigenstate on which dipolar order develops with assist of an additional portion of RF field designed to implement adiabatic demagnetization in the nutating frame.

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Kohei Suzuki, Kazuyuki Takeda. 2025-06-27. First-order nuclear dipolar order in rotating solids. https://arxiv.org/abs/2506.21916

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