Fabrication 3-dimensional ferromagnetic-plasmonic nanostructures and the application as high-efficiency magnetooptical materials

研究了经红外飞秒激光辐照后的a-Fe_2O_3掺杂透明玻璃的光学、磁学和磁光性质。辐照后玻璃的室温饱和磁化强度较未辐照样品有所提高，这是由于铁氧体纳米粒子的析出所致。通过进一步添加掺杂作为等离子体金属的前驱体，Au或Al纳米粒子在辐照和热退火后与铁氧体纳米粒子一起在一个受限区域内空间选择性地析出。在Al共掺杂的情况下，磁光Faraday效应得到了增强，并出现了一个负峰，这是由于铁氧体纳米粒子的亚磁性和Al纳米粒子的局域表面等离子体共振之间的耦合所致。

Optical, magnetic, and magneto-optical properties have been investigated for the a-Fe2O3-doped transparent glasses irradiated with an infrared femtosecond laser and subsequently annealed. The values of the saturation magnetization at room temperature for the irradiated glasses were increased compared with the as-prepared samples, which is due to the precipitation of the ferrimagnetic ferrite nanoparticles (NPs). By adding further dopants as precursors of plasmonic metals, Au or Al NPs were space-selectively precipitated together with the ferrite NPs in a confined region after irradiation and thermal annealing. In the case of the glass codoped with Al, magneto-optical Faraday effect was enhanced and exhibited a negative distinct peak ascribed to a coupling between the ferrimagnetism of ferrite NPs and the localized surface plasmon resonance of Al NPs.