One-magnon inelastic light scattering in the canted antiferromagnet NiF2

Experimental results concerning the temperature and polarization dependence of the one-magnon Raman light scattering in the canted antiferromagnet NiF2 (Neel temperature T-N = 73 K) are reported. The excitation frequencies, linewidths, and integrated intensities of the lower and upper magnon branches are obtained over the temperature range 5-65 K. A comparison between theory and experiment for the frequencies of the one-magnon branches shows good overall agreement for temperatures up to 0.3T(N). A theoretical model that includes the effects of linear and quadratic magneto-optical coupling is used to account for the observed polarization characteristics of the Stokes and anti-Stokes peaks. The analysis takes account of the small canting angle of the spins which complicates the behavior of the lower magnon branch, in particular. The experimental data are indicative of a possible spin-reorientation transition at similar to 31 K.