Two-dimentional Surface Plasmonic Grating Optical Absorbers Based On Disk Strings

The electron density wave, which spreads along the surface of metal, is called surface plasmon. It is caused by the interaction of the free vibration of electron and photon on the surface of metal. At present, people are trying to fabricate optical absorber based on surface plasma, the optical absorber has very extensive application prospect in the aspects of thin film solar cell.Firstly, the research background and significance of the optical absorber are introduced when the research trends of grating light absorber are summarized. Subsequently, the computing method is expounded in this paper. Finally, the two kinds of two-dimensional surface plasmon grating optical absorbers are designed, and the influences of structure parameters on the absorption properties are studied in detail.The specific contents are as follows:(1) The radius of metal disk of the string, the center distance between the metal disk strings and the layer of metal disks of the string are simulated in detail while the effect on the absorption properties of 2D surface plasmonic grating optical absorber based on metal disk strings is analyzed. Absorption properties under the structure parameters of optimization are provided finally. The calculation results show that the effect of the layer of metal disks on absorption properties is largest in the visible range. The absorption reaches saturation state when the layer of metal disks of the string exceeds 50. The radius of metal disk and the center distance between the metal disk strings tune it slightly. The absorption effect can be obviously improved by making the center distance between the metal disk strings decrease linearly from the center to left and right sides.(2) The layer of the air disks the string, the radius of the air disk, the center distance between adjacent air disk strings and the center distance between adjacent air disks of the string are discussed in detail when the effect on the absorption properties of 2D surface plasmonic grating optical absorber based on air disk strings is analyzed. Absorption properties under the structure parameters of optimization are provided finally. The effect of the layer of the air disks on the absorption rate in the visible range is remarkable. The more layers of the air disks have, the better the absorption effect will be. However, this trend will be gentle with the increasing of the layer. The radius of the air disk, the center distance between adjacent air disk strings and the center distance between adjacent air disks of the string influence each other in the condition of fixed layers.The work of this paper provides the theory for design, fabrication and application of surface plasmon grating light absorber.