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Most liquids, when supercooled, freeze into a glassy state. The nature of this transition is one of the outstanding puzzles in condensed matter physics. The notion of an entropy vanishing transition underlying the glass transition was proposed a few decades ago by Adam and Gibbs. Recent experiments and simulations have demonstrated the presence of `dynamical heterogeneities'' in a supercooled liquid near the glass transition. We have been studying frustrated spin models which shows a connection between extended spatial structures and the divergence of time-scales which accompanies the glass transition).
Through numerical studies of a variation of the triangular Ising antiferromagnet, we have shown that an entropy vanishing transition involving extended spatial structures can lead to glassy dynamics and a Vogel-Fulcher divergence of timescales. [1]
In more recent work, we have shown that the Vogel-Fulcher divergence of time scales can be explained in terms of topological jamming.
It is tempting to speculate that such structures are forced into supercooled liquids by the frustrations inherent in the system and that the glass transition owes its origin to an underlying instability towards the disappearance of these structures.
These are some animations for pure TIAFM in a rhomboid system. The first two animations describe the equilibrium evolutions of the system, when the spin configurations are characterized by 2/3 string density. The last two animations describe the relaxation processes starting from an initial zero string density state, which is an ordered state. In all the graphics, the defects are the yellow triangles with two orientations. Fast spins are the filled red circles. Strings are the clustering of the fast spins in vertical direction.
Caution: Each file is approximately 2.5 megs.
