Active Control of Dipole-Exchange Coupled Magnon Modes in Nanoscale Bicomponent Magnonic Crystals

Abstract

Bicomponent magnonic crystals (BMCs) are metasurfaces formed using two dissimilar materials, which offer a richer manipulation of spin waves and promising spin-wavebased computation, communication, and signal processing. Here, the intricate interplay of spin dynamics between two different materials Co 50 Fe 50 and Ni 80 Fe 20 forming a BMC is exploited experimentally. Optimally engineered interface leads to interelement exchange coupling combined with the long-range dipolar coupling as confirmed by micromagnetic simulations. These couplings have been further tuned by systematic variation of the filling fraction of Co 50 Fe 50 and Ni 80 Fe 20 in the BMC. Moreover, the characteristic properties of spinwave spectra are found to be highly sensitive to the bias-field strength. Further numerical simulations based on experimentally determined parameters demonstrate long-distance and high-speed spin-wave propagation in such BMCs controlled by the filling fraction and offer a diode-like on/off mechanism determined by the applied magnetic field strength. These observations will lead to the development of high-speed reconfigurable magnonic devices controlled by external parameters.

Tunable strong magnon-magnon coupling in two-dimensional array of diamond shaped ferromagnetic nanodots

“…In view of the above knowledge, here we have explored magon-magnon coupling in diamond-shaped Py nanodot array with the aid of a broadband ferromagnetic resonance (FMR) spectrometer [36][37][38][39] and micromagnetic simulations. We have aimed to investigate the role played by the internal field inside the diamond dots and the inter-element interaction fields in the magnon modes and their intermodal coupling.…”