Rigidity Transition in Chalcogenide Glasses: Dynamic Nano-Indentation and Diffuse Reflectance Spectroscopic Studies

Rigidity Transitions in quaternary glasses were investigated using dynamic nanoindentation and DRS reflectance spectroscopy in Ge 15Te 80-xIn 5Ag x glasses. In quasi-static properties such as reduced modulus, E r and hardness, H, an extended rigidity transition with distinct floppy, intermediate and rigid phase is observed, while indentation toughness, K c and brittleness index, BI exhibits a rigidity transition at x =12. Floppy modes exhibit higher K c values when compared to rigid modes. Dynamic visco-elastic property, storage modulus vs frequency, f exhibits a trend reversal for floppy and rigid phases, which is attributed to difference in heat losses. The manifestation of intermediate phase (IP) in optical band gap E g) is observed in the composition range (8 ≤ x ≤ 14) at. %.