Generic <i>α</i> relaxation in a strong <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>GeO</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math> glass melt

Abstract

The viscoelastic α relaxation in glass-forming GeO_{2} was measured over a range of temperatures near the glass transition using photon correlation spectroscopy. The relaxation in this "strong" glass former exhibits a nonexponential decay identical to that found in a great many simple organic "fragile" liquids. This finding contradicts the longstanding conjecture that nonexponentiality of viscous relaxations near the glass transition are correlated to the liquid's fragility. Instead, the findings offer support for a recent proposal that the nonexponentiality parameter of the α-relaxation in supercooled liquids displays a universal value β(T_{g})=1/2 near the glass transition.

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