![]() studied the optical bistability of the random composites with nonlinear metallic nanoparticles. developed the self-consistent mean-field approximation to study the nonlinear composite media consisting of coated nanoparticles with nonlinear core and nonlinear shell. Moreover, for the three-dimensional nonlinear composite consisting of the core-shell nanostructures, the nonlinearity of the whole composite system can be dramatically enhanced by adjusting the material properties of core-shell particle composition ratio Furthermore, Gao et al. For instance, researchers found that the two-dimensional nonlinear composites exhibit huge enhancement of the third-order nonlinear optical susceptibility under the partial resonant condition. In addition, studies of nonlinear susceptibilities generated by two (three) harmonics in isotropic (or anisotropic) composite systems with core-shell nanoparticles were also widely investigated. For metal/semiconductor core-shell structure composite system, it was found that there exists large enhancement of the optical nonlinear susceptibility. With the development of nanotechnology, preparation of some special microstructures such as core-shell nanoparticle becomes possible. It is well-known that the local field enhancement of composite system may result in the optical bistability, which can be adjusted by controlling the local microstructure and the physical parameters of components in the composite system. For two-component nonlinear composite system, variational methods and self-consistent mean-field approximation were developed to investigate the nonlinear response of composite system and to explore optical bistable behavior. Optical bistability has attracted widespread interests for decades, due to its novel feature of controlling light with light. This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Our results may be helpful for the design of the nonlinear device with appropriate bistability. Therefore, the optical bistability for nonlinear composite materials may be optimized by the suitable adjustment of the physical and geometrical parameters. It is found that the optical bistability appears only when the core radius and the incident frequency satisfy some specific conditions. We demonstrate that the bistability threshold and the bistable width are highly dependent on the core radius, the incident frequency, and the graded coefficient of the coated cylinder inclusion. We derive the nonlinear equation of near field for such graded composite in the quasistatic limit. The intrinsic optical bistability of the nonlinear composite consisting of coated cylinders with nonlinear core and graded Drude shell is investigated with self-consistent mean-field approximation. * e-mail: e-mail: online: 23 November 2020 School of Science, Jiangnan University, Wuxi 214122, PR China
0 Comments
Leave a Reply. |