Preparation and investigation of structure, optical, nonlinear optical and thermoelectric properties of Bi2Se3 thin film

Bi2Se3 thin film was prepared using thermal evaporation . Structure and surface topography were investigated both of Diffraction Electron Microscope (DEM) Transmission (TEM). Optical results confirmed that has a direct energy gap. Moreover, the values for all oscillating (Eo), dispersion (Ed) ratio free carrier concentration on effective mass (N/m*) determined optically. The dielectric constant (ε\) tangent loss calculated. density states (DOS) valence band (Nv) conduction (Nc) also position Fermi level determined. nonlinear optical such as third-order susceptibility (χ(3)), refractive index (n2) absorption coefficient (βc) influence temperature IV studied; finally dependence Dispersion factor (D), parallel inductance (Lp) Seebeck (S) this studied.