Static and dynamic magnetic properties of Ni80Fe20 anti-ring nanostructures

作     者：J. Ding N. Singh M. Kostylev A. O. Adeyeye 

作者机构：Information Storage Materials Laboratory Department of Electrical and Computer Engineering National University of Singapore Singapore 117576 A*Star Institute of Microeletronics 11 Science Park Road Singapore Science Park II Singapore 117685 School of Physics University of Western Australia Crawley Western Australia 6009 Australia 

出 版 物：《Physical Review B》 (物理学评论B辑：凝聚态物质与材料物理学)

年 卷 期：2013年第88卷第1期

页      面：014301-014301页

核心收录：

学科分类：07[理学] 0702[理学-物理学] 

基　　金：SMF-NUS Ministry of Education, Singapore Australian Research Council 

主　　题：MAGNETIC properties MAGNETIC entropy STATIC electricity FERROMAGNETIC resonance KERR electro-optical effect 

摘      要：The static and dynamic behavior of Ni80Fe20 anti-ring arrays has been systematically investigated using broadband ferromagnetic resonance (FMR) spectroscopy, magneto-optical Kerr effect (MOKE), and magnetic force microscopy (MFM). The unit cell of this periodic lattice represents a hole in a continuous film, with an elliptical nanodot placed in the middle of the hole. The FMR responses display multiple absorption peaks due to the superposition of the absorptions from the anti-dot and the central nanomagnet (dot) regions of the anti-ring structures. Interestingly, for fixed anti-ring geometry, the static and dynamic behavior is markedly sensitive to the thickness of the structure due to complicated spatial distributions of the demagnetizing field. Direct MFM imaging reveals that at remanence, the central nanomagnets are in a single-domain state, for small sample thicknesses, whereas for larger thicknesses, they display a multidomain or vortex state. This observation is in good agreement with both FMR and MOKE data. All our results agree well with micromagnetic simulations.