Magnon Signal Research Articles

Light scattering from two-magnon modes in K 2NiF 4

Measurements of Raman scattering from two magnon excitations in the two dimensional antiferromagnet K 2NiF 4 are extended to 275°K. The zeroth frequency moment of the magnon signal has a temperature dependence essentially the same as that found in the three dimensional antiferromagnet, NiF 2. No indications of critical behavior are apparent in the first frequency moment for K 2NiF 4 in contrast to the case of three dimensional antiferromagnets.