nuclear magnetic resonance study of a high-concentration Mn-doped ZnO system was carried out.
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Mn-ion impurity and the proton dipole-dipole relaxation contributions were well resolved.
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Ferromagnetic exchange interaction was associated with the impurity relaxation mechanism and activation of interstitial H.
Abstract
In our 1H nuclear magnetic resonance study of a high-concentration Mn-doped ZnO system, the Mn-ion impurity and the proton dipole-dipole relaxation contributions were well resolved. In particular, a change at 290 K in the magnetic susceptibility showing a weakening of the ferromagnetic exchange interaction was accompanied by that in the impurity relaxation mechanism and by activation of the high-temperature hopping motion of interstitial H. Thus, a unique opportunity has been provided to elucidate the role of hydrogen in the ferromagnetic coupling in the Mn-doped ZnO systems.