A modulated differential scanning calorimetric study of As–Te–In glasses

Network topological thresholds in gallium doped As–Te glasses – Electrical and thermal investigations

“…The increase in the glass transition temperatures of As 20 Te 80Àx Ga x glasses in the composition range 7.5 6 x 6 15 is suggestive of an increase in network connectivity with the addition of Ga atoms. A similar increase in T g with composition has been seen in few other As-Te-III glasses such as As-Te-In, As-Te-Al, in which the III group atoms enter the covalent network having four fold or higher coordination, thereby increasing the network connectivity and rigidity [4,5].…”

“…As-Te-Al samples, on the other hand, exhibit a composition dependent electrical switching (memory/threshold) [3]. The composition dependence of switching voltages (V T ) and thermal parameters of As-Te-III glasses also shows interesting differences; switching voltages and thermal parameters such as glass transition temperature (T g ) of As-Te-In and As-Te-Al glasses exhibit an increase with the addition of III group atoms [4,5]. However, V T and T g of As-Te-Tl samples show a decrease with the increase in thallium content [2].…”

Chemical ordering and fragility minimum in Cu–As–Se glasses

“…Ge 20 Se 70Àx Te 10 Bi x glasses also exhibit a minimum in DC p at the chemical threshold (x = 7.5 at.% of Bi) [32]. Similarly, a minimum in DC p is seen in As 40 Te 60Àx In x glasses at x = 15 which corresponds to the chemical threshold of these glasses [33]. Ge-Sb-Se, Ge-As-Te and Si-As-Te glasses also exhibit a minimum in DC p at the chemical ordering threshold [34].…”

High pressure studies on the electrical resistivity of As–Te–bond Si glasses and the effect of network topological thresholds

“…They have identified the minimum observed at r = 2.65 (x = 12.5) with RPT and the minimum at r = 2.7 (x = 15) with CT. Modulated differential scanning calorimetric measurements on the As−Te−In system [18] also indicate RPT at r = 2.65 and CT at r = 2.7. No signature of the intermediate phase was found in these glasses.…”