Double magnonic chains of particles: Spin waves slowing and snaking

• Published in: Journal of magnetism and magnetic materials 2020-04, Vol.500, p.166351, Article 166351
• Main Authors: Pikalov, Anton M., Dorofeenko, Alexander V., Granovsky, Alexander B.
• Format: Article
• Language: English
• Subjects: Chain scission; Chains; Dipole interactions; Group velocity; Magnetic moments; Magnetic particles; Magnonic switch; Magnonic waveguides; Magnons; Particle spin; Spin waves; Transmittance; Yttrium-iron garnet
• ISSN: 0304-8853; 1873-4766
• DOI: 10.1016/j.jmmm.2019.166351

•Dispersion relations for magnon waves in a single and double chains of spherical magnetic particles.•Low group velocity of the spin waves.•Group velocity can be controlled by the chain parameters.•Spin wave snaking between the two chains.•Magnonic switcher can be built based on the double magnonic chain. We calculated the dispersion relations for magnon waves in a single and two adjacent periodic chains of spherical magnetic particles magnetized along the chain axis. Dipole-dipole coupling between point magnetic moments in a chain and between chains was taken into account. A weak coupling between local magnetic moments at separate particles in a chain leads to formation of narrow transmittance band, which results in a low group velocity of the spin waves. The group velocity can be controlled by the chain parameters. In the case of double magnon chains, a transmittance band splits into two sub-bands corresponding to symmetric and anti-symmetric eigenmodes. Interference between them results in spin wave snaking between the two chains. This effect is field-dependent that makes possible application of double chains of magnetic particles in magnonic switch.