Optical and Glass Stability Parameters of Ge–Te–Se–Sb Chalcogenide Glasses for Optical Data Storage

The present work describes the glass stability parameters of quaternary GeTe_{2 – x}(SeSb)_x (x = 0, 0.2, 0.4, 0.6) chalcogenide glasses. The thin-film samples of thickness ~500 nm was deposited by thermal evaporation technique. DSC analysis of GeTe_2–x(SeSb)_x chalcogenide glasses for studying different glass stability criteria at various heating rate (β = 5, 10, 15 and 20°C/min) were carried out. Many optical parameters of GeTe₂ studied by UV-vis and glass stability parameters like H_LL, H_MM, H_CS, etc. were determined. These criteria can be attained by the interrelationship between the characteristic temperatures. According to the onset and peak crystallization temperature, two groups of these criteria were investigated. The value of absorption coefficient is larger than 104 cm, therefore it is useful for optical data storage. The optical band gap energy is observed at 2.834 eV and material has direct allowed transition. The refractive index is observed to be increased with increase in wavelength. All investigated parameters revealed that studied composition is suitable for optical data storage applications.