A key nonlinear effect in magnonics is the three-magnon splitting where a high-frequency magnon splits into two magnons of lower frequencies. Here, we study the three-magnon splitting in spin-wave conduits made from synthetic antiferromagnets. By combining inductive excitation, inductive detection, Brillouin light scattering imaging of the spin waves and analytical modeling based on conservation laws, we elucidate the nature of the spin waves involved in this process. We show in particular that low-order optical spin waves propagating along the conduit can split in doublets of nondegenerate acoustic spin waves that have a standing-wave character in the confined direction and unsymmetrical wave vectors in the direction of the spin-wave conduit. Generally, several splitting channels run in parallel. The rules governing the three-magnon splitting and its interplay with the mode confinement have consequences for the applications in nonlinear microwave signal processing based on spin waves.

Close

PrevNext

View figure in article

• Frequency conversion
• Magnonics
• Spin optoelectronics
• Spin waves
• Synthetic antiferromagnetic multilayers
• Waveguides
• Microwave techniques
• Room temperature RF