Abstract
We report preliminary low-field (2 mT and 0.1 T) NMR measurements on room temperature laser polarised 3He gas imbibed into a 98% porous silica aerogel. The hyperpolarised helium is introduced into the cell in which the aerogel had been grown, and large NMR signals can be recorded. Long polarisation lifetimes ( T 1≃50 s) have been observed, revealing a very weak specific wall relaxation in the cell. NMR of hyperpolarised 3He gas is thus a potential tool to measure physical parameters inside the aerogels which are used to study quantum fluids in confined geometries. This has been demonstrated using a multi-echo technique to characterize spin diffusion in an applied magnetic field gradient. Spin diffusion was found to be isotropic and its pressure dependence was studied. An estimate of the mean free path for gas atoms in the aerogel is deduced from this behaviour.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
