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arXiv · 0705.0667

Generating Unexpected Spin Echoes in Dipolar Solids with Pi Pulses

Dale Li·A. E. Dementyev·Yanqun Dong·R. G. Ramos·S. E. Barrett
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Abstract

NMR spin echo measurements of C-13 in C60, Y-89 in Y2O3, and Si-29 in silicon are shown to defy conventional expectations when more that one pi pulse is used. Multiple pi-pulse echo trains may either freeze our or accelerate the decay of the signal, depending on the pi-pulse phase. Average Hamiltonian theory, combined with exact quantum calculations, reveals an intrinsic cause for these coherent phenomena: the dipolar coupling has a many-body effect during any real, finite pulse.

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Dale Li, A. E. Dementyev, Yanqun Dong, R. G. Ramos, S. E. Barrett. 2007-05-04. Generating Unexpected Spin Echoes in Dipolar Solids with Pi Pulses. https://doi.org/10.1103/physrevlett.98.190401

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