【摘 要】
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Using model analysis and first-principles calculations,we have performed a systematic investigation on the passivants effect on the structural stabilities of SixGe1-x nanowires.With various passivants
【机 构】
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Department of Physics,South China University of Technology,Guangzhou 510640,People's Republic of Ch
【出 处】
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第十二届国际凝聚态理论与计算材料学会议(The 12th International Conference on Con
论文部分内容阅读
Using model analysis and first-principles calculations,we have performed a systematic investigation on the passivants effect on the structural stabilities of<110> SixGe1-x nanowires.With various passivants,such as fluorine(F),chlorine(CI),or hydrogen(H)atoms,Si atoms prefer to segregate towards the surface of nanowires due to the stronger Si-X bonds than that of Ge-X bonds(X=F,C1,H).It is noteworthy that the diameter and shape of most stable SixGe1-x nanowires are determined by the composition x and the passivants chemical potential.In addition,the composition profile of Si and Ge atoms was obtained by minimizing the Gibbs free energy and the method of estimating the entropy is also demonstrated.Our finding provides a practical avenue to tune the electronic properties of SixGe1-x nanowires,by modulating the morphologies of nanowires with the composition control of Si/Ge and the chemical potential of passivants.
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