High-pressure studies on the critical composition in Ge—As—Te glasses

Abstract

High-pressure resistivity measurements have been performed on Ge_7·5As_xTe_92·5-x. (x = 20, 40, 45, 50 and 55) and Ge₁₀As_xTe_90-x(x= 15, 20, 35, 40, 45 and 50) glasses. The glasses show reversible metallization behaviour under pressure. The pressure derivative of the logarithm of the resistivity of the glasses is a minimum at glass compositions corresponding to the average coordination number 〈r〉 = 2·60. This behaviour is interpreted on the basis of the existence of a critical composition in glasses with a layered structure.