研究生: |
王俊凱 Wang, Chun-Kai |
---|---|
論文名稱: |
CuB2O4晶體在第一原理的研究 Ab initio study of the anti-ferromagnetic, non-collinear CuB2O4 crystal |
指導教授: |
陳穎叡
Chen, Yiing-Rei |
學位類別: |
碩士 Master |
系所名稱: |
物理學系 Department of Physics |
論文出版年: | 2019 |
畢業學年度: | 107 |
語文別: | 中文 |
論文頁數: | 31 |
中文關鍵詞: | 第一原理 、晶體結構 、能帶分析 |
英文關鍵詞: | first-pronciple, CuB2O4, non-collinear calculation |
DOI URL: | http://doi.org/10.6345/THE.NTNU.DP.001.2019.B04 |
論文種類: | 學術論文 |
相關次數: | 點閱:171 下載:24 |
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研究CuB2O4反鐵磁性材料在第一原理中的能帶架構以及材料特性。
CuB2O4在第一原理中,使用六個單元的方式呈現週期性的結構分布,在這個晶格中a=11.357、c=5.542 Å, k-mesh使用4x4x4, nbands為400 並且使用VASP GGA+U的方法,其中Cu(A)&Cu(B)的U分別為U1=6.4eV, U2=7.0eV。
在計算中,我們發現CuB2O4的density of state(DOS)在導帶的地方會出現兩個非常明顯的尖點。一個是由Cu(A)&O(1)組成,另外一個則是由Cu(B)&O(2)&O(3)&O(4)所貢獻,因此我們希望可以分析出兩者的不同。
Ab initio study of anti-ferromagnetic non-collinear CuB2O4 crystal ,CuB2O4 crystallizes in first-principles calculations, with six formula units were performed using periodic density function theory. The cell of dimensions a=11.357 and c=5.542 Å, k-mesh=4x4x4, nbands=400 and use GGA+U on VASP where U1=6.4eV, U2=7.0eV for Cu(A)&Cu(B).In the case, we found that CuB2O4’s density of state(DOS) has two peaks in conduction band. One is contributed by Cu(A) & O(1), the other one is contributed by Cu(B) & O(2) & O(3) & O(4). As the result of, we can sort atoms to two types. A type is Cu(A) and O(1) which donate states to peak(1), the other type is Cu(B) and O(2)&O(3)&O(4) which donate states to peak(2). And we could do analyze their difference.
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