The cooperative migration dynamics of particles correlates to the nature of hexatic-isotropic phase transition in 2D systems of corner-rounded hexagons  

作　　者：Zhanglin Hou Mingwei Liu Yiwu Zong Fangfu Ye Kun Zhao 

机构地区：[1]Wenzhou Institute,University of Chinese Academy of Sciences,Wenzhou,Zhejiang 325001,China [2]Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(Ministry of Education),School of Chemical Engineering and Technology,Tianjin 300072,China [3]School of Physical Science,University of Chinese Academy of Sciences,Beijing 100049,China [4]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [5]Oujiang Laboratory(Zhejiang Lab for Regenerative Medicine,Vision and Brain Health),Wenzhou,Zhejiang 325001,China [6]Sichuan Provincial People’s Hospital,University of Electronic Science and Technology of China,Chengdu,Sichuan 610054,China [7]Institute of Fundamental and Frontier Sciences,University of Electronic Science and Technology of China,Chengdu,Sichuan 610054,China

出　　处：《Fundamental Research》2024年第2期284-290,共7页自然科学基础研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(11874277,21621004 and 12104453);the Strategic Priority Research Program of Chinese Academy of Sciences(XDB33030300).

摘　　要：In the two-dimensional(2D)melting transition of colloidal systems,the hexatic-isotropic(H-I)transition can be either first-order or continuous.However,how particle dynamics differs at the single-particle level during these two different melting transitions remains to be disclosed.In this work,by Brownian dynamics(BD)simulations,we have systematically studied the dynamic behavior of corner-rounded hexagons during the H-I transition,for a range of corner-roundness𝜁=0.40 to 0.99 that covers the crossover from the continuous to first-order nature of H-I transition.The results show that hexagons with𝜁≤0.5 display a continuous H-I transition,whereas those with𝜁≥0.6 demonstrate a first-order H-I transition.Dynamic analysis shows different evolution pathways of the dominant cluster formed by migrating particles,which results in a droplet-like cluster structure for𝜁=0.40 hexagons and a tree-like cluster structure for𝜁=0.99 hexagons.Further investigations on the hopping activities of particles suggest a cooperative origin of migrating clusters.Our work provides a new aspect to understand the dependence of the nature of H-I transition on the roundness of hexagons through particle dynamic behavior.

关 键 词：Melting transition COLLOIDS Hexatic phase Cooperative migration HEXAGONS 

分 类 号：O17[理学—数学]