Polaritons in nanocomposites of metal nanoparticles - dielectric

The article studies the main characteristics of surface polaritons in composite nanomaterials. The authors consider composite media such as noble metal nanoparticles randomly distributed in a transparent dielectric matrix and build dispersion curves of polaritons in such nanocomposites. The paper shows calculating optical parameters of thesurfacepolariton for several values of the radius of metal nanoparticles and the nanocomposite filling parameter. The authors also present the calculations of the complex refractive index for polaritons in composites with nanoparticles of different metals. In addition, the authors find the dependences of the real and imaginary parts of the complex refractive index of the nanocomposite on the normalized frequency for membranes with different thicknesses and calculate real and imaginary parts of dielectric constant for waves in several metals. Besides, the article provides an overview of important stages in the study of surface electromagnetic waves. It shows that the variation of the structure materials, size and concentration of nanoparticles opens widepossibilities for controlling theoptical properties of compositemediums and their practical application. Theconsidered nanocomposites areartificially created media whose material parameters can be controlled. The first method consists in changing the relative volume of the nanoparticles filling of the dielectric matrix. The second method consists in changing the dielectric constant of the nanocomposite matrix. The authors emphasize that the dielectric constant of the nanocomposite in this case acquires resonant properties in contrast to the permeability of the nanoparticles themselves.