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Measurement of persistence in 1D diffusion

Glenn P. Wong·Ross W. Mair·Ronald L. Walsworth·David G. Cory
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Abstract

Using a novel NMR scheme we observed persistence in 1-D gas diffusion. Analytical approximations and numerical simulations have indicated that for an initially random array of spins undergoing diffusion, the probability p(t) that the average spin magnetization in a given region has not changed sign (i.e., ``persists'') up to time t follows a power law t^{-θ}, where θ depends on the dimensionality of the system. Using laser-polarized ^{129}Xe gas, we prepared an initial ``quasirandom'' 1D array of spin magnetization and then monitored the ensemble's evolution due to diffusion using real-time NMR imaging. Our measurements are consistent with analytical and numerical predictions of θ\approx 0.12.

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Glenn P. Wong, Ross W. Mair, Ronald L. Walsworth, David G. Cory. 2001-07-09. Measurement of persistence in 1D diffusion. https://doi.org/10.1103/physrevlett.86.4156

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