The Theoretical Research On Sicnts Photoelectric Properties

One dimensional nanotubes become the frontier in the field of low dimensional nanometer materials research. In recent years, the silicon carbide nanotubes(Si CNTs) research are widely valued. In order to explore the relationship between the diameter sizes of Si CNTs and the physical properties of Si CNTs, In this paper, the calculations of the two kinds of chiral Si CNTs of different sizes are simulated with the first principles. In order to explore the impurity defects on the physical properties of(6,6)Si CNTs, simulations of different models which a X(X = B, Al, Ga, In) in the III group respectively for a doping of the silicon atom in the same position in all(6,6)Si CNTs in this paper are calculated. The main contents are summarized as follows:First of all, the background and progress of the Si CNTs are briefly expounded and the material structures and the purpose and content of the study are briefly introduced. The theoretical foundation and calculation methods of first principles calculation are simply introduced.Secondly, two kinds of chiral Si CNTs models in different sizes are optimized by the CASTEP module based on the density functional theory. And their structural parameters, electronic and optical parameters are calculated. The results indicate that the stability of two kinds of chiral Si CNTs with increasing tube diameter size and all Si CNTs can be made into light or light detector of purple light sensitive.Finally, the structural parameters, electronic properties and the main optical properties of puer(6, 6) Si CNTs and the(6, 6) Si CNTs doped by the third main group elements are calculated and analyzed in this paper. The results indicate that the(6, 6) Si CNTs are semiconductors whether they are pure or doped, the doped(6, 6) Si CNTs are p-type doped semiconductor and the doped(6, 6)Si CNTs can be prepared for infrared photosensitive semiconductor devices.The unusual propertits of Si CNTs present a more broad application space in photoelectric device, microelectronics, aerospace and other fields.