Precessing Ball Solitons in Kinetics of a Spin-Flop Phase Transition

The fundamentals of precessing ball solitons (PBS), arising as a result ofthe energy fluctuations during spin-flop phase transition induced by a magneticfield in antiferromagnets with uniaxial anisotropy, are presented. The PBSconditions exist within a wide range of amplitudes and energies, includingnegative energies relative to an initial condition. For each value of themagnetic field, there exists a precession frequency for which a curve of PBSenergy passes through a zero value (bifurcation point), and hence, in thevicinity of this point the PBS originate with the highest probability. Thecharacteristics of PBS, including the time dependences of configuration,energy, and precession frequency, are considered. As a result of dissipation,the PBS transform into the macroscopic domains of a new phase.