On the problem of optical bistability of nonlinear composites with coated inclusions

• Date: 2001
• Main Authors: Grechko, L. G., Davidova, O. A., Mal'nev, V. N., Whites, K. W.
• Format: Article
• Language: English
• Published: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2001
• Online Access: https://surfacezbir.com.ua/index.php/surface/article/view/56
• Journal Title: Surface

The electrodynamical properties of the nonlinear metal composites are intensively studied in many papers [1-7]. One of the most important property of such systems is the abnormal enhancement of the nonlinear optical respond in the composites containing small inclusions (compared to the wavelength of radiation) of a nonlinear dielectric covered by the metal shell embedded in a dielectric host matrix [2-6]. The surface plasmons in the metal shell may be tuned in resonance with the external electromagnetic field and produce a considerable increase in the local field in the core of inclusion to make the nonlinear part of its dielectric permittivity to be important. As a result, the connection between the applied and the local field in the core becomes nonlinear and in some diapason of applied electric fields even ambiguous. It happens to be that one value of the applied field corresponds to a few values of the local fields and polarization of the inclusions that in its turns leads to instability in the composite optical properties. This phenomenon is called the intrinsic optical bistability (IOB). In this paper we calculate the dielectric permittivity and polarizability of a separate inclusion_and analyze the parameters of the IOB. Further, we consider the dielectric function of