Gauge theory approach to glass transitions

This theory combines a thermodynamic approach with a dynamic one in order to describe glass transition. Glass transition is regarded as an inaccessible second order phase transition, which is interrupted because of premature critical slowing down, caused by the system's frustration. The frustration-induced vortices are present in the structure besides thermoactivated vortices, and prevent the development of the order parameter fluctuations, that leads to the critical slowing down the system kinetics at some temperature above the phase transition point

About causes of slow relaxation of melted intermetallic alloys

Ascertainment of the nature of the slow relaxation processes observed after melting in glass-forming eutectic melts is the subject of this work. We claim that the diffusion processes nonlinearity in heterogeneous melt with inclusions of refractory stoichiometry is the origin of this phenomenon. The cause for this nonlinearity is the thermodynamic instability similar to one taking place at spinodal decomposition, and indispensable condition is the initially non-homogenous. For confirmation of our devotes, we consider the model of liquid solution of a binary system, which evolution described by the Cahn-Hilliard equation with combined Gibbs potential assuming the presence of remains after melting stoichiometric phase. Exemplified by the Al-Y and Al-Yb alloys, using Gibbs potentials from a standard database we show that subject to initial heterogeneity in these systems the instability can develop leading to the slow relaxation processes, and determine the regions of this instability in the phase diagrams

To understanding of slow and non-monotonic relaxation in Al–Y eutectic melts

We discuss the nature of slow relaxation processes in glass-forming eutectic melts right after melting. For specific, we focus on the binary metallic melt Al–Y, which in addition to the slow relaxation shows unusual non-monotonic dynamics. We argue this slow dynamic the result of non-linearity of diffusion processes in the initially non-homogenous sample, and the nature of slow relaxation processes in eutectic melts after melting is similar to the nature of spinodal decomposition when the reason for the slowdown is the thermodynamic instability. To support this assertion we considered the model with combined Gibbs potential of the Al-Y liquid solution, in which the presence of the stoichiometric phase remains is taken into account. We show that in this system the instability mathematically described by the Cahn–Hilliard type equation can develop, and that fluctuation accounting in the considered model allows qualitatively describe the non-monotonic relaxation observed in the Al-based non-equilibrium melts. © 2020 Elsevier B.V.The work was supported by the Russian Foundation for Basic Research , Grants 18-02-00643 (MV) and 18-42-180002 (VL). Part of the work was carried out within the framework of the state assignment of the Ministry of Education and Science of Russia (no. AAAA-A17-117022250039-4 )