Reconfigurable magnonic mode-hybridisation and spectral control in a bicomponent artificial spin ice

• Published in: Nature communications Vol. 12; no. 1; p. 2488
• Main Authors: Gartside, Jack C., Vanstone, Alex, Dion, Troy, Stenning, Kilian D., Arroo, Daan M., Kurebayashi, Hidekazu, Branford, Will R.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 03.05.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 142/126; 142/136; 147/135; 147/3; 639/301/357/997; 639/766/119/2793; 639/766/119/997; 639/925/357/1015; Arrays; Coupling; Crystals; Host systems; Humanities and Social Sciences; Hybridization; Magnons; multidisciplinary; Nanotechnology; Reconfiguration; Remanence; Science; Science (multidisciplinary); Spectra; Spectral control; Spin ice
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-22723-x

Strongly-interacting nanomagnetic arrays are finding increasing use as model host systems for reconfigurable magnonics. The strong inter-element coupling allows for stark spectral differences across a broad microstate space due to shifts in the dipolar field landscape. While these systems have yielded impressive initial results, developing rapid, scaleable means to access a broad range of spectrally-distinct microstates is an open research problem. We present a scheme whereby square artificial spin ice is modified by widening a ‘staircase’ subset of bars relative to the rest of the array, allowing preparation of any ordered vertex state via simple global-field protocols. Available microstates range from the system ground-state to high-energy ‘monopole’ states, with rich and distinct microstate-specific magnon spectra observed. Microstate-dependent mode-hybridisation and anticrossings are observed at both remanence and in-field with dynamic coupling strength tunable via microstate-selection. Experimental coupling strengths are found up to g /2 π  = 0.16 GHz. Microstate control allows fine mode-frequency shifting, gap creation and closing, and active mode number selection. Reconfigurable magnonic crystals (RMC), comprising nano-patterned arrays of magnetic elements, can host a wide variety of spectrally-distinct microstates with great potential for functional magnonics. Here, Gartside et al, present an RMC with four distinct microstates, possessing diverse magnonic properties and exhibiting reconfigurable magnon mode hybridisation.