Attraction Controls the Entropy of Fluctuations in Isosceles Triangular Networks

作者：Leoni Fabio; Shokef Yair^*

来源：Entropy, 2018, 20(2): 122.

DOI：10.3390/e20020122

• order by disorder
• geometric frustration
• confined colloids
• residual entropy

We study two-dimensional triangular-network models, which have degenerate ground states composed of straight or randomly-zigzagging stripes and thus sub-extensive residual entropy. We show that attraction is responsible for the inversion of the stable phase by changing the entropy of fluctuations around the ground-state configurations. By using a real-space shell-expansion method, we compute the exact expression of the entropy for harmonic interactions, while for repulsive harmonic interactions we obtain the entropy arising from a limited subset of the system by numerical integration. We compare these results with a three-dimensional triangular-network model, which shows the same attraction-mediated selection mechanism of the stable phase, and conclude that this effect is general with respect to the dimensionality of the system.

• 出版日期2018-2