Dec 6, 2012
Micromagnetic simulations examine non-monotonic spin-wave tunneling across a barrier
Studies on the spin wave spectrum of confined magnetic structures have opened up a new subfield of magnetism dubbed magnonics that deals with spin-wave properties in a periodic magnetic structure – the so-called magnonic crystal.
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.
About the author
Dr XiangJun Xing is currently an assistant professor at Wenzhou University and was previously a PhD student of Sun Yat-sen University under the supervision of Prof. Dr ShuWei Li. After earning his doctorate, Xing went to Wenzhou University where he is a research member of the Institution of Micro-Nano Structures and Optoelectronics. His research interests cover spin dynamics of confined magnetic structures, preparation and characterization of magnetic films, biological magnetism, and plasmonics.