A new artificial spin ice lattice called vortex lattice is proposed based on the Kagome lattice. Monte Carlo simulations were performed to investigate the magnetization reversal process of the new artificial spin ice lattice at external magnetic field and different lattice parameters. The results demonstrate some interesting phenomena which are different from Kagome lattice. There are four typical sub-structures emerged in the vortex lattice, which are clockwise and counter-clockwise hexagons, and frustrated +3q and -3q vertices. The occurrence frequency of the four sub-structures change dramatically at different lattice parameter. The new lattice can be partially frustrated at different lattice parameter.

We design and fabricate a substrate based on a three-dimensional array–film hybrid structure used for surface enhanced Raman scattering (SERS). This substrate exhibits improvements both in sensitivity and homogeneity for the Raman signals. As a result, the substrate increases the Raman signal of Rhodamine 6G by 12.3 times under the same measurement conditions, compared with conventional gold array sitting directly on a silica wafer. The sensitivity of SERS can be easily tuned by changing the thickness of SiO2 separation. Meanwhile, the relative standard deviations are achieved to be less than 10%. This array–film hybrid structure provides a promising approach for future SERS applications.

We calculate the photon absorption coefficient of hot two-dimensional electrons in the presence of a strong magnetic field. The electrons interact strongly with the optical phonons and the acoustic phonons in quantum wells. The dependence of the optical absorption on the magnetic field is obtained by using the quantum mechanical kinetic theory. It is found that the photon absorption spectrum displays a local magnetophonon resonance. The magnetophonon absorption resulting from inelastic scattering between Landau levels is more pronounced at higher temperature. The effect of subband nonparabolicity on the absorption coefficient is also discussed.