INVESTIGATION OF THE SPECTRAL DEPENDENCE OF OPTICAL ABSORPTION IN A GLASSY Ge-As-Se-S CHALCOGENIDE SYSTEM BY MATHEMATICAL CONSISTENCY METHOD
S.M. Mammadov
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ABSTRACT

In this work, the spectral dependence of the optical absorption coefficient (α) was measured for various compositions of the Ge-As-Se-S glassy system, and a comparative mathematical fitting of the experimental dependence with the Belehradek functional relation was carried out. It was established that deviations of the inverse value of the power exponent n in the Tauc relation [(α·hν)1/n ~f(hν)] from m = 0.5 are associated with the departure of the energy dependence of the density of states from that of free-electron states, which is explained by the fractal characteristics of the investigated materials.

Keywords: chalcogenide glass, amorphous, fractal
DOI:10.70784/azip.2.2025310

Received: 04.09.2025
Internet publishing: 10.09.2025    AJP Fizika A 2025 03 az p.10-16

AUTHORS & AFFILIATIONS

Institute of Physics Ministry of Science and Education Republic of Azerbaijan, 131 H.Javid ave, Baku, AZ-1073, Azerbaijan
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