近年來研究者在籠目晶格(Kagome)反鐵磁性的FeGe材料中發現，當系統溫度下降至110K時，FeGe會發生電荷密度波(Charge Density Wave, CDW)的現象。密度泛函理論(Density Functional Theorem, DFT)計算指出，電荷密度波的形成會導致FeGe產生2×2×1的超週期性扭曲結構。FeSn與FeGe的晶格結構與磁性類似，卻未在實驗或是理論預測中發現電荷密度波的存在，這使得研究者們好奇是否能透過摻雜或加壓等方式誘發FeSn中潛在的電荷密度波。在本篇研究中，我們透過密度泛函理論計算FeSn摻雜磷、砷、銻等元素的結構能量差異、能帶結構、聲子譜，發現33%砷摻雜會促使FeSn產生電荷密度波。

Researchers have recently discovered that the Kagome lattice antiferromagnetic material FeGe exhibits charge density wave (CDW) when the system's temperature drops to 110K. Density Functional Theorem (DFT) calculations indicate that the formation of CDW leads to a 2×2×1 superperiodic distorted structure in FeGe. FeSn shares a similar lattice structure and magnetism with FeGe, yet no CDW has been observed experimentally or predicted theoretically in FeSn. Despite the absence of CDW in FeSn, exploring ways to induce the potential CDW in FeSn, such as doping or applying strain, remains a fascinating research topic. In this study, we performed DFT to calculate the structural energy differences, band structures, and phonon spectra of FeSn doped with elements such as phosphorus (P), arsenic (As), and antimony (Sb). The results reveal that 33% arsenic doping promotes the formation of CDW in FeSn.

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