arXiv:cond-mat/0411613 · Journal of Experimental and Theoretical Physics Letters

Exact results on spin dynamics and multiple quantum NMR dynamics in alternating spin-1/2 chains with XY Hamiltonian at high temperatures

Edward B. Fel’dman, M. G. Rudavets

Published Jan 1, 2005• 33 citations

Abstract

We extend the picture of a transfer of nuclear spin-1/2 polarization along a homogeneous one-dimensional chain with the XY Hamiltonian to the inhomogeneous chain with alternating nearest neighbor couplings and alternating Larmor frequencies. To this end, we exactly calculate the spectrum of the spin-1/2 XY Hamiltonian of the alternating chain with an odd number of sites. The exact spectrum of the XY Hamiltonian is also applied to study the multiple quantum (MQ) NMR dynamics of the alternating spin-1/2 chain. MQ NMR spectra are shown to have the MQ coherences of zero and ± second orders just as in the case of a homogeneous chain. The intensities of the MQ coherences are calculated.

DOI: 10.1134/1.1887913

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