Electrical resistivity of Cu doped As-Se glasses at high pressure

Electrical resistivity measurements have been performed on CuxAs40Se60–x glasses with x between 0 and 28 at% of Cu. The resistivity of these glasses continuously decreases and saturates at higher quasi‐hydrostatic pressures. The pressure derivative of the electrical resistivity shows distinct changes as a function of composition; a large change for the initial addition of Cu (≤ 10 at% Cu) and levelling off for higher content of Cu. To understand this, Differential Scanning Calorimetric (DSC) and thermal crystallization studies have been carried out on all these glasses. Thermal crystallization of As–Se glasses with 5 and 10 at% Cu results in crystalline Cu3AsSe4 and As2Se3 phases, whereas glasses with 15 and 20 at% of Cu crystallize into Cu3AsSe4 phase only. Glasses with 25 and 28 at% of Cu yield a new binary Cu2As3 and the ternary Cu3AsSe4 phase. These structural differences arising as a function of composition are reflected in the pressure derivative of the resistivity of the glasses.