Search results for "Nickel oxides"

Behavior of one-magnon frequency in antiferromagneticNicMg1−cOsolid solutions

2005

The one-magnon scattering was studied in antiferromagnetic ${\mathrm{Ni}}_{c}{\mathrm{Mg}}_{1\ensuremath{-}c}\mathrm{O}$ solid solutions. We observed unpredicted behavior of both temperature and composition dependences of one-magnon excitation energies. First, the abrupt change of the one-magnon frequency by $7--8\phantom{\rule{0.3em}{0ex}}{\mathrm{cm}}^{\ensuremath{-}1}$ occurs between $c=0.98$ and $c=0.9$ in the limit of $T\ensuremath{\rightarrow}0\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. Second, upon increasing temperature, the one-magnon energy for highly diluted nickel oxide vanishes significantly below the N\'eel temperature.