Tunable Magneto-Optical Kerr Effects of Nanoporous Thin Films

Abstract

Magnetoplasmonics, combining magnetic and plasmonic functions, has attracted increasing attention owing to its unique magnetic and optical properties in various nano-architectures. In this work, Ag, CoFeB and ITO layers are fabricated on anodic aluminum oxide (AAO) porous films to form hybrid multi-layered nanoporous thin films by magnetron sputtering deposition process. The designed nanostructure supports localized surface plasmon resonance (LSPR) and tunable magneto-optical (MO) activity, namely, the sign inversion, which can be controlled by AAO porous film geometry (pore diameter and inter-pore spacing) flexibly. The physical mechanism of this special MO phenomena is further analyzed and discussed by the correlation of Kerr rotation and electronic oscillations controlled by the surface plasmon resonance that is related to the nanoporous structure.

Tailoring of Perpendicular Magnetic Anisotropy in Dy13Fe87 Thin Films with Hexagonal Antidot Lattice Nanostructure

“…These artificial arrays have been recently used in ultra-high density data storage applications [ 7 ], where the antidot lattices allow to define a peculiar type of bit patterned media that can overcome the superparamagnetic limit due to the non-formation of isolated magnetic domains [ 8 ], in addition to magnetic bio-sensing applications [ 9 ], among many others. Moreover, they attract notable attention due to their capacity to act as metamaterials (magnonic crystals), where the antidots exhibit a periodic potential for magnons, allowing for the control of spin wave dispersion [ 10 , 11 ]. The recently reported nanostructured material based on the exchange coupled bicomposite formed by Co. dots embedded in a matrix of NiFe antidot arrays, where the soft ferromagnetic properties of the NiFe antidots influence the vortex nucleation field of Co. dots, can modify the magnetotransport and spin wave properties of the system [ 12 ].…”

Visualizing hydrogen diffusion in magnetic film through magneto-optical Kerr effect

“…Based on these findings, we also observed appreciable magnetic modulation in Pd-rich magnetic alloy thin films, indicating that such materials would be useful in fabricating gas sensors and especially suitable for spatially resolved hydrogen diffusion 12,[18][19][20][21][22][23] . Moreover magneto-optical Kerr effect (MOKE), originating from the optical property and magnetism of materials, has long been widely applied in magnetic measurement of nanoscale samples because of the extremely high sensitivity and feasibility [24][25][26] . In addition to the magneto-optical Kerr rotation and intensity, the intrinsic characteristics of magnetism such as the magnetic cercivity H c and the squareness M r /M s can be measured through this method 14,16,18,23,27,28 .…”

Metal-Free Oxide-Nitride Heterostructure as a Tunable Hyperbolic Metamaterial Platform

“…Considering the AFM nature of NiO, it is proposed that, under high magnetic field, the spins at nanorod boundaries are completely polarized such that the inner AFM domain being probed acts as counteractive effect and reduces further enhancement of the Kerr signal. In general, these substantial variations by comparing the magnetometry hysteresis loops (Figure a,b) with MO Kerr loops (Figure c,d) suggest a correlation between both diagonal and off-diagonal terms of the dielectric function with the change of magnetic field, ,− which are valuable for further investigations. It is also noted that the coupling between diagonal dielectric tensors with magnetization of such hybrid metamaterial could be of great importance toward applications in ultrafast switching, magnetic storage, sensors, and circuit designs. , …”