Speaker
Description
Artificial spin ice (ASI) is a particular class of magnetic metamaterials where geometrical arrangement of single domain nano magnets well-defined lattices leads to degeneracy of low energy states and frustration. It has recently been shown that artificial spin ices can be considered as potential candidates for reprogrammable magnonic crystals [1-3]. Therefore, we have endeavored an extensive characterization of the spinwave dynamics of ASI. Specifically, we have determined the tunable spinwave dynamics in the “trident lattice” ASI geometry where three nanomagnet (trident) building blocks are periodically arranged in a perpendicular fashion [4]. We have measured the spinwave dynamics using our time-resolved magneto-optical Kerr effect microscope (TR-MOKE), which has spatial resolution of ~ 1 µm and temporal resolution of 50 fs. The experimental observations show that the spinwave spectra of the trident ASI system changes significantly as a function of applied external magnetic field. One single spinwave mode splits into two modes with the decrease of the external magnetic field. The experimental results are well reproduced and explained by micromagnetic simulations. These observations are important for potential applications in future spinwave based magnonic devices.
References:
1. M. Krawczyk and D. Grundler, J. Phys.: Condens. Matter 26, 123202 ( 2014)
2. S. Gliga, et al. Phys. Rev. Lett. 110, 117205 (2013)
3. E. Iacocca, S. Gliga, et al., Phys. Rev. B (2016) 93, 134420 (2016)
4. A. Farhan et al., Nat. Com, 8, 995 (2017)
