arXiv 1012.33092010-12-15cond-mat.mes-hall

Si $_{n}$ Ge $_{n}$纳米线超晶格多量子阱结构中的束缚态

Confined states in multiple quantum well structures of Si$_{n}$Ge$_{n}$ nanowire superlattices

Nurten Akman, Engin Durgun, Seymur Cahangirov, Salim Ciraci

备注：: please find published version in here: http://link.aps.org/doi/10.1103/PhysRevB.76.245427
发表信息：: Phys. Rev. B 76, 245427 (2007)
DOI：: 10.1103/PhysRevB.76.245427

摘要：

采用第一性原理赝势平面波方法研究了Si $_{n}$ Ge $_{n}$纳米线超晶格的力学性质、原子能带结构和氢钝化后的能带结构.未掺杂的四面体Si和Ge纳米线片段赝晶连接，可以形成具有原子级尖锐界面的超晶格。我们发现Si $_{n}$纳米线比Ge $_{n}$纳米线更硬。氢钝化使得这些纳米线和Si $_{n}$ Ge $_{n}$纳米线超晶格甚至更坚硬。在异质结构形成时，超晶格电子态在动量空间中形成子带。Si和Ge区的带排列导致多个量子阱，其中带边缘和带连续区中的特定状态被限制。纳米线超晶格的电子结构取决于组成Si和Ge段的长度和截面几何形状。由于裸露的Si和Ge纳米线是金属的，并且氢化纳米线的带隙随直径而变化，Si $_{n}$ Ge $_{n}$超晶格为多量子阱器件提供了许多替代方案，其引线由组成金属纳米线制成。

英文摘要：

Mechanical properties, atomic and energy band structures of bare and hydrogen passivated Si$_{n}$Ge$_{n}$ nanowire superlattices have been investigated by using first-principles pseudopotential plane wave method. Undoped, tetrahedral Si and Ge nanowire segments join pseudomorphically and can form superlattice with atomically sharp interface. We found that Si$_{n}$ nanowires are stiffer than Ge$_{n}$ nanowires. Hydrogen passivation makes these nanowires and Si$_{n}$Ge$_{n}$ nanowire superlattice even more stiff. Upon heterostructure formation, superlattice electronic states form subbands in momentum space. Band lineups of Si and Ge zones result in multiple quantum wells, where specific states at the band edges and in band continua are confined. The electronic structure of the nanowire superlattice depends on the length and cross section geometry of constituent Si and Ge segments. Since bare Si and Ge nanowires are metallic and the band gaps of hydrogenated ones varies with the diameter, Si$_{n}$Ge$_{n}$ superlattices offer numerous alternatives for multiple quantum well devices with their leads made from the constituent metallic nanowires.

机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。

摘要：

英文摘要：

相关论文