Modeling of Multilayer Structures with Tunable Optical Characteristics

Phase-transition materials, in particular chalcogenide glassy semiconductors and Ge–Sb–Te system materials, are of interest for application in optical information-processing technologies. The uniqueness of these materials lies in the fact that they have a low-energy, and fast and reversible phase transition, which leads to a significant change in the refractive index in the infrared region of the optical spectrum. The model calculations carried out in the work make it possible to investigate the transformation of the optical properties in multilayer structures consisting of SiO2, Si, Si3N4 layers and the active layer of a phase transition material when its phase state changes. The aim of these studies is to fulfill the condition of the lowest optical losses during the transmission and reflection of radiation of 1550 nm in such structures in the case of amorphous and crystalline states of the active layer, respectively. As a result, a nine-layer structure “SiO2//111 nm Si/277 nm SiO2/ 111 nm Si/251 nm SiO2/10 nm Ge2Sb2Se4Te/241 nm SiO2/110 nm Si/276 nm SiO2/112 nm Si//SiO2”, which satisfies the specified conditions to the greatest degree, is designed.