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arXiv:quant-ph/9808041 · Physical review. B, Condensed matter

Quantum coherence oscillations in antiferromagnetic chains

M. Grigorescu, Mahi R. Singh

Published Mar 1, 1999• 0 citations
arXivHTMLPDF

Abstract

Macroscopic quantum coherence oscillations of the N\'eel vector are proved to appear in the antiferromagnetic nuclear spin chain of eight ${}^{129}\mathrm{Xe}$ atoms placed on a magnetic surface. The oscillation period at zero temperature is calculated numerically as a function of the chain constant. The environmental decoherence effects at finite temperature are accounted assuming a dipole coupling between the spin chain and the fluctuating magnetic field of the surface. With this coupling the N\'eel vector oscillations are damped by a rate $(N\ensuremath{-}1)/\ensuremath{\tau},$ where N is the number of spins and $\ensuremath{\tau}$ is the relaxation time of a single spin.

DOI
10.1103/physrevb.59.6013

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