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Quantum Dynamical Echoes in the Spin 'Diffusion' in Mesoscopic Systems

Horacio M. Pastawski·Patricia R. Levstein·Gonzalo Usaj
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Abstract

The evolution of local spin polarization in finite systems involves interference phenomena that give rise to {\bf quantum dynamical echoes }and non-ergodic behavior. We predict the conditions to observe these echoes by exploiting the NMR sequences devised by Zhang et al. [Phys. Rev. Lett. {\bf % 69}, 2149 (1992)], which uses a rare $^{13}$C as {\bf local probe }for a dipolar coupled $^1$H spin system. The non-ideality of this probe when testing mesoscopic systems is carefully analyzed revealing the origin of various striking experimental features.

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Horacio M. Pastawski, Patricia R. Levstein, Gonzalo Usaj. 1996-04-03. Quantum Dynamical Echoes in the Spin 'Diffusion' in Mesoscopic Systems. https://doi.org/10.1103/physrevlett.75.4310

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