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arXiv · 0710.3567

Nonlinear NMR dynamics in hyperpolarized liquid 3He

Emmanuel Baudin·Michael E. Hayden·Geneviève Tastevin·Pierre-Jean Nacher
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Abstract

In a highly polarized liquid (laser-polarized 3He-4He mixtures in our experiment), dipolar magnetic interactions within the liquid introduce a significant nonlinear and nonlocal contribution to the Bloch equation that leads to instabilities during NMR evolution. We have launched a study of these instabilities using spin echo techniques. At high magnetizations, a simple 180 degree rf pulse fails to refocus magnetization, so we use a standard solid-state NMR pulse sequence: the magic sandwich. We report an experimental and numerical investigation of the effect of this sequence on unstable NMR evolution. Using a series of repeated magic sandwich sequences, the transverse magnetization lifetime can be increased by up to three orders of magnitude.

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Emmanuel Baudin, Michael E. Hayden, Geneviève Tastevin, Pierre-Jean Nacher. 2007-11-28. Nonlinear NMR dynamics in hyperpolarized liquid 3He. https://arxiv.org/abs/0710.3567

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