Au/Ag nanoshuttles with sharp tips at both ends have been synthesized in glycine solution by chemically depositing silver on gold nanorods. Strong local field in the Au/Ag nanoshuttles enhanced by longitudinal surface plasmon resonance (LSPR) were investigated by theoretical calculations and experimental measurements. At the corresponding LSPR wavelengths, the extinction cross section and nonlinear refraction of the Au/Ag nanoshuttles are about 1.5 and 8.0 times of those of the original Au nanorods, respectively.

Fe/Hf multilayers were prepared by alternate deposition of pure hafnium and iron. As-deposited samples were then annealed at 380 °C and 550 °C, respectively, to investigate the microstructure and magnetic property changes of the films. It was found that all as-deposited Fe/Hf films exhibited the soft ferromagnetic property where the coercive force was lower than 30 Oe. The coercive force and the magnetic moment per Fe atom changed significantly with the annealing temperature and the Fe layer thickness (tFe ). For tFe = 2.2-4.2 nm films, their soft ferromagnetic properties were stable upon thermal annealing at 380 and 550 °C, while for tFe 9.5 nm and tHf = 13.2 nm films, after annealing at 550 °C for 20 min, as-deposited films transformed from having a soft ferromagnetic property to having a hard ferromagnetic one. The residual magnetization and maximum magnetic energy product of the films could come up to about 0.81 µB and 8.8 kJ m-3 (1.1 MGOe), for the Fe(9.5 nm)/Hf(13.2 nm) films annealed at 550 °C. It was also found that there were two metastable phases with fcc structure in the annealed Fe-Hf films. The magnetic change mechanism was discussed in terms of interdiffusion in the Fe/Hf interface and phase transformation in the films upon thermal annealing.