Kravets Vasyl G, Lapchuk Anatoliy S
Institute for Information Recording, National Academy of Sciences of Ukraine, Shpak Str. 2, Kiev, 03113 Ukraine.
Appl Opt. 2010 Sep 10;49(26):5013-9. doi: 10.1364/AO.49.005013.
We report enhanced magneto-optical Kerr rotation in the layer systems of a magnetic granular film coated by uniform gold and dielectric films. The Kerr rotation spectra measured from 1.2 to 5 eV show a peak at about 2.7 eV, not present in either uncoated magnetic particle films. It was shown that the polar magneto-optical Kerr signal is about five times higher than that obtained for CoFe-MgO granular films in similar conditions. The physical nature of the magneto-optical effect enhancement in three layers (magnetic/noble/dielectric films) is related to the excitation of surface plasmons and their fast propagation on the interface of a complex three-layer structure. The Kerr rotation enhancement corresponds to intrinsic electronic transitions in the CoFe nanogranules due to the spectral overlap of these transitions with propagating surface plasmons.
我们报道了在由均匀金膜和介电膜包覆的磁性颗粒膜层系统中增强的磁光克尔旋转。从1.2到5电子伏特测量的克尔旋转光谱在约2.7电子伏特处出现一个峰值，这在未包覆的磁性颗粒膜中均不存在。结果表明，在类似条件下，极化磁光克尔信号比CoFe-MgO颗粒膜所获得的信号高约五倍。三层结构（磁性/贵金属/介电膜）中磁光效应增强的物理本质与表面等离子体激元的激发及其在复杂三层结构界面上的快速传播有关。由于这些跃迁与传播的表面等离子体激元的光谱重叠，克尔旋转增强对应于CoFe纳米颗粒中的本征电子跃迁。
