Spin waves in one-dimensional bi-component quasicrystals

TL;DR

This paper investigates the complex spin wave behavior in one-dimensional Fibonacci quasicrystals made of Co and Py stripes, revealing fractal spectra, localized modes, and surface waves through theoretical modeling.

Contribution

It introduces a continuous model for magnonic quasicrystals that accounts for exchange and dipole interactions, demonstrating their fractal spectra and localized spin wave modes.

Findings

Magnonic spectrum exhibits fractal structure with multiple gaps.

Spin waves can be localized within the quasicrystal.

Surface spin waves exist in finite quasicrystal structures.

Abstract

We studied finite Fibonacci sequence of Co and Py stripes aligned side-by-side and in direct contact with each other. Calculations based on continuous model including exchange and dipole interactions were performed for structures feasible for fabrication and characterization of main properties of magnonic quasicrystals. We have shown the fractal structure of the magnonic spectrum with a number of magnonics gaps of different width. Also localization of spin waves in quasicrystals and existence of surface spin waves in finite quaiscrystal structure is demonstrated.