R. Golovchak, H. Jain, O. Shpotyuk, A. Kozdras, A. Saiter and J.-M. Saiter.
Physical review B, vol. 78, 2008, p. 014202.
Physical aging effects caused by prolonged natural storage (~22 years) in binary AsxSe100−x glasses are probed by temperature-modulated differential scanning calorimetry. It is shown that all aged samples with x < 40 reveal nonzero out-of-phase component of complex heat flow testifying physical aging effect. The first composition, which can be attributed to a so-called self-organized phase characterized by the absence of natural physical aging effect, is the stoichiometric As2Se3 glass; lack of aging within the so-called reversibility window, 28 < x < 38, is not found. High-resolution x-ray photoelectron spectroscopy fails to show any evidence of fourfold-coordinated As atoms, which is consistent with the aging ability of glasses with x < 40.