In recent work, researchers from Wenzhou University and Sun Yat-sen University in China have used micro-magnetic simulations to investigate spin-wave tunneling through an air gap opened in a magnetic strip.

They found that the spin wave transmission rate is strongly related to the coupling state of the edge magnetization beside the gap. Equally, it does not decay monotonically when the width of the mechanical gap is increased, for certain special coupling states.

These results have dropped an essential hint on the design of a class of magnonic crystals built on an array of magnetic elements. Namely, that the mutual edge-magnetization configuration might strongly influence the magnon spectrum.

By providing a re-excitation picture of spin waves in the edge domain behind the gap, the scientists have offered a consistent explanation of the state-dependence and the non-monotonicity of the spin-wave tunneling.

Full details can be found in the journal Nanotechnology.