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NMR Time Reversal Experiments in Highly Polarised Liquid 3He-4He Mixtures

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 نشر من قبل Pierre-Jean Nacher
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Emmanuel Baudin




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Long-range magnetic interactions in highly magnetised liquids (laser-polarised 3He-4He dilute mixtures at 1 K in our experiment) introduce a significant non-linear and non-local contribution to the evolution of nuclear magnetisation that leads to instabilities during free precession. We recently demonstrated that a multi-echo NMR sequence, based on the magic sandwich pulse scheme developed for solid-state NMR, can be used to stabilise the magnetisation against the effect of distant dipolar fields. Here, we report investigations of echo attenuation in an applied field gradient that show the potential of this NMR sequence for spin diffusion measurements at high magnetisation densities.



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