Search citation statements
Paper Sections
Citation Types
Year Published
Publication Types
Relationship
Authors
Journals
In the present paper, the effect of low-temperature annealing on the linear optical properties of disordered thin films (~350 nm) synthesized from Ge10Se90 glass by vacuum thermal evaporation on quartz substrates is reported. Based on the experimental transmission spectra of films in the field of optical transparency before and after annealing below and at the glass transition temperature Tg = (3612) K (313 and 363 K, respectively), the main optical characteristics (dispersion dependences of the refractive index and extinction coefficient, optical gap energy, the Tautz parameter B1/2, etc.) were determined using the Swanepoel and Tautz methods. It is revealed that the edge of optical absorption in the annealed films is caused by indirect optical transitions. Using the Wemple-DiDomenico single oscillator model, the Urbach energy EU, the energy of one oscillator E0, the scattering energy Ed, the linear susceptibility and the static refractive index n0 were calculated. At the same time, a higher value of the Ed/E0 ratio of the film annealed at Tg indicates its greater nonlinear susceptibility. The X-ray diffraction studies have confirmed the amorphous nature of the initial films and the appearance of Se nanocrystallites in them after annealing of a certain polymorphic modification depending on the temperature and time of annealing. It was found that annealing both below Tg and at Tg initiates red shift in the optical absorption edge, an increase in EU and , and a decrease in the thickness of the film and the parameter B1/2. It is shown that the annealing of identical films is accompanied by a change in their phase composition with the appearance of either monoclinic beta-Se8 nanocrystallites or the mixture of beta-Se8 and trigonal t-Se. From the standpoint of the concept of the polymerpolymorphoid structure of glass and a glass-forming liquid, it is due to the mutual transformation of polymorphoids of various polymorphic modifications because of a change in their concentration ratio depending on the annealing temperature relative to Tg. The resulting films can be used in optoelectronics as nonlinear optical elements or media for radiation limiters.
In the present paper, the effect of low-temperature annealing on the linear optical properties of disordered thin films (~350 nm) synthesized from Ge10Se90 glass by vacuum thermal evaporation on quartz substrates is reported. Based on the experimental transmission spectra of films in the field of optical transparency before and after annealing below and at the glass transition temperature Tg = (3612) K (313 and 363 K, respectively), the main optical characteristics (dispersion dependences of the refractive index and extinction coefficient, optical gap energy, the Tautz parameter B1/2, etc.) were determined using the Swanepoel and Tautz methods. It is revealed that the edge of optical absorption in the annealed films is caused by indirect optical transitions. Using the Wemple-DiDomenico single oscillator model, the Urbach energy EU, the energy of one oscillator E0, the scattering energy Ed, the linear susceptibility and the static refractive index n0 were calculated. At the same time, a higher value of the Ed/E0 ratio of the film annealed at Tg indicates its greater nonlinear susceptibility. The X-ray diffraction studies have confirmed the amorphous nature of the initial films and the appearance of Se nanocrystallites in them after annealing of a certain polymorphic modification depending on the temperature and time of annealing. It was found that annealing both below Tg and at Tg initiates red shift in the optical absorption edge, an increase in EU and , and a decrease in the thickness of the film and the parameter B1/2. It is shown that the annealing of identical films is accompanied by a change in their phase composition with the appearance of either monoclinic beta-Se8 nanocrystallites or the mixture of beta-Se8 and trigonal t-Se. From the standpoint of the concept of the polymerpolymorphoid structure of glass and a glass-forming liquid, it is due to the mutual transformation of polymorphoids of various polymorphic modifications because of a change in their concentration ratio depending on the annealing temperature relative to Tg. The resulting films can be used in optoelectronics as nonlinear optical elements or media for radiation limiters.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.