Breaking of symmetry and the establishment of order at non-equilibrium phase transitions in glasses

Abstract

The experiments in which glass becomes anisotropic under the action of uniaxial pressure or weakly absorbed polarized light and, beyond the critical light threshold, demonstrates the formation of gigantic lattices and gigantic non-crystalline clusters, are analyzed from the point of view of non-equilibrium phase transitions (NPT) in open systems. For the first time the appearance of macroscopic order in the initially isotropic glass is connected with the breaking of symmetry. It is shown that these NPT may be considered using synergetics notions such as the order parameter and dimension of the order parameter, dissipative patterns and critical thresholds. The effect of electronic switching in glassy semiconductors (Ovshinsky effect) is also considered as NPT. Based on these ideas the new aspects of structure and properties of glass are discussed.