NMR Time Reversal as a Probe of Incipient Turbulent Spin Dynamics

NMR Time Reversal as a Probe of Incipient Turbulent Spin Dynamics
M. E. Hayden,1 E. Baudin,2 G. Tastevin,2 and P. J. Nacher2

1Physics Department, Simon Fraser University, 8888 University Drive, Burnaby BC, Canada V5A 1S6
2Laboratoire Kastler Brossel, Ecole Normale Supérieure; CNRS; UPMC; 24 rue Lhomond, F75005 Paris, France
Phys. Rev. Lett. 99, 137602 (2007)
(Received 23 April 2007; published 27 September 2007)

We demonstrate time reversal of nuclear spin dynamics in highly magnetized dilute liquid ³He-⁴He mixtures through effective inversion of long-range dipolar interactions. These experiments, which involve using magic sandwich NMR pulse sequences to generate spin echoes, probe the spatiotemporal development of turbulent spin dynamics and promise to serve as a versatile tool for the study and control of dynamic magnetization instabilities. We also show that a repeated magic sandwich pulse sequence can be used to dynamically stabilize modes of nuclear precession that are otherwise intrinsically unstable. To date, we have extended the effective precession lifetimes of our magnetized samples by more than three orders of magnitude.

(Thanks to Louis Bouchard for sending...Curt)