Exchange Integral in Cobalt from Spin-Wave Resonance

The exchange constant $A$ and exchange integral $J$, and their temperature dependences, have been measured in cobalt metal films by spin-wave resonance. At room temperature, $A=1.30\mathrm{}\times {10}^{-6\mathrm{}}$ erg/cm and $J=155k$. $J$ is temperature independent between 4°K and 295°K. Comparison is made with recent data obtained by other experimental methods.