Chaotic regimes of antiferromagnetic resonance in a quasi-two-dimensional easy-axis antiferromagnet (NH₃)₂ (CH₂)₄ MnCl₄

الأصل · EN

Chaotic regimes of the microwave energy absorption are experimentally observed and analyzed for two-dimensional metallorganic antiferromagnet (NH₃)₂(CH₂)₄MnCl₄ at low temperatures under the conditions of nonlinear antiferromagnetic resonance. Relaxation oscillations of energy absorption are investigated in detail. Their frequency spectra, frequency-amplitude characteristics, and dependences of absorbed power on driving power and static magnetic field are studied. It is shown that the dynamics of relaxation oscillations undergoes a transition to chaos by "irregular periods". Peculiarities of the transition are described consistently. Among other things, the conditions for the emergence of energy absorption regimes with a spike-like and a saw-tooth signal structure are determined, and the characteristics of chaotic oscillations such as the dimensions of strange attractors are calculated. The chaotic dynamics is found to be high-dimensional with a large contribution from noise which is of deterministic origin in the antiferromagnet under investigation.