Spin-fluctuation spectrum, phase relaxation, and NMR of β-active 8Li nuclei in LiF crystals: from the method of memory functions to cumulant expansions
Bulgakov M. I. , Gul'ko A. D. , Dzheparov F. S. , Stepanov S. V. , Trostin S. S.
The magnetic-resonance shape function g(cu) of impurity /З-active Li nuclei has been measured in LiF by /З-NMR spectroscopy. The external magnetic field was oriented along the [001], [Oil], and [111] axes of the single crystals in different measurements. The function g(<a) varies over nearly five orders of magnitude. The hypothesis of normal fluctuations of the local magnetic field at impurity nuclei, combined with the general principles of the theory of irreversible processes, leads to a quite general and elementary description of the phase relaxation of these nuclei. This description is convenient for interpreting experiments.