標題: | 多鏈數的準一維維格納晶體的結構躍遷及溶解行為 Structural Transition and Melting Dynamics of Quasi-One-Dimensional Wigner Crystal with Large Numbers of Chains |
作者: | 曹君碩 Tsao, Chun-Shuo 增原宏 Hiroshi Masuhara 應用化學系分子科學碩博士班 |
關鍵字: | 準一維;維格納;結構躍遷;Quasi-One-Dimensional;Wigner Crystal;Structural Transition |
公開日期: | 2015 |
摘要: | 我們研究用理論的方式來探討在準一維維格納晶體[1]上的一些性質,在較低密度上,一些基本的特性已經被研究[2][3]過了,在高密度上我們按照他們的方式來進行研究。我們利用分析計算與數值模擬的方式來得到不同的基態結構,在分析計算中,我們發現有些不規則的躍遷,在數值模擬當中,我們發現有三種不同型態的結構分別是,完美結構,與兩種不同的缺陷結構。在低密度的情況下,基態結構幾乎已完美結構的方式呈現,在高密度的情況下則以一種缺陷結構為主體。我們模擬在有限溫度下的溶解行為,發現到他與溶解的方向有很大的關係。在x方向的不同的融解可以歸因於不同型態的基態機構,而在y方向的融解行為則與是否在一個擁有多個躍遷點的小密度區間有關。 We studied theoretically properties of a quasi-one-dimensional (Q1D) Wigner crystal [1]. Properties of Q1D Wigner crystal in low densities are studies in Refs [2] and [3]. Following their treatment we investigated high density region. We performed analytical calculation and numerical simulations to obtain different ground state structures. In the analytical calculation, we found that there exist some abnormal structural transitions. In the numerical simulation, we found the three different types structures, perfect structure and two different types of defective structures. In low density region, the ground state structures are mostly perfect, and a type of defective structure is dominant in high densities. We simulated the dynamics of electrons at finite temperatures to discuss the melting behavior. We found a clear direction dependence. In the x direction, melting behavior is determined by the types of structures. The y-direction melting depends on whether it is in a small region having more than one structural transition points. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#GT070152404 http://hdl.handle.net/11536/127422 |
Appears in Collections: | Thesis |