Universal Long-Time Behavior of Nuclear Spin Decays in a Solid

Abstract

Magnetic resonance studies of nuclear spins in solids are exceptionally well suited to probe the limits of statistical physics. We report experimental results indicating that isolated macroscopic systems of interacting nuclear spins possess the following fundamental property: spin decays that start from different initial configurations quickly evolve towards the same long-time behavior. This long-time behavior is characterized by the shortest ballistic microscopic time scale of the system and therefore falls outside of the validity range for conventional approximations of statistical physics. We find that the nuclear free-induction decay and different solid echoes in hyperpolarized solid xenon all exhibit sinusoidally modulated exponential long-time behavior characterized by identical time constants. This universality was previously predicted on the basis of analogy with resonances in classical chaotic systems.

Multidimensional Mapping of Spin-Exchange Optical Pumping in Clinical-Scale Batch-Mode 129Xe Hyperpolarizers

“…Regardless of the polarization method, HP noble gases have seen wide application varying from fundamental physics experiments 31−34 to NMR/MRI applications including molecular biosensors, 35−37 probing structural aspects of cage molecules and proteins, 18,38−43 and studies of porous materials (to name only a few). 15,45−47 However, it has been biomedical applications that have largely driven the development of hyperpolarized MR techniques over the past decade; indeed, for gas imaging in particular, HP 129 Xe can be used to assess lung function and report on functional and microstructural abnormalities.…”

Long-lived selective spin echoes in dipolar solids under periodic and aperiodicπ-pulse trains

“…The fine structure could be the result of some sort of orientation selection under the CPMG(Y, Y ) pulse train 34,35 or possibly a consequence of exponentially damped, sinusoidal modulations in the FID recently observed in dipolar soilds 36 . Further experimental work needs to be performed in order to characterize these spectral features in adamantane.…”

Robust solidXe129longitudinal relaxation times

“…pressure of hyperpolarized xenon [10,33,34]. These cells were made by mixing naturally abundant xenon with xenon that is isotopically enriched in spinless isotopes.…”