Attraction Controls the Entropy of Fluctuations in Isosceles Triangular Networks

Entropy

Yair Shokef¹  Fabio Leoni¹ 

[1] School of Mechanical Engineering, Tel-Aviv University, Tel-Aviv 69978, Israel;

关键词: order by disorder;    geometric frustration;    confined colloids;    residual entropy;   

DOI  :  10.3390/e20020122

来源: DOAJ

【 摘 要 】

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.

【 授权许可】

Unknown