Kinetics of parametric instability of spin waves in an antiferromagnet
Smirnov A.I.
The growth of the number of magnons nk in the course of their parametric excitation was investigated experimentally. It turned out that during the initial stage of the process nk grows exponentially. The instability increment is smaller by a factor 2.5 than the value that follows from the simple model in which the damping is taken into account phenomenologically.