Synthesis, solid-state NMR, and magnetic characterization of h-GaN containing magnetic ions

GaN crystals doped with Mn ions were synthesized by the alkali metal flux method. Mixtures of metals were premelted to form an alloy and the alloy was mixed with Na/K and heated to ∼800 °C under ∼1400 psi N2 in an alumina crucible. Up to 2 mol% Mn could be incorporated into the h‐GaN lattice, and the products were characterized by solid state NMR, magnetometry, Raman spectroscopy, and powder X‐ray diffraction. The solid state MAS NMR spectra (71Ga, 69Ga, 14N) of the most heavily doped material, which is a normal paramagnet, have broad peaks that are shifted appreciably to higher frequency from the hexagonal GaN chemical shift position, probably due to Knight shifts. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)