Nanoelectronics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) , Tsukuba Central 5, 1-1-1 Higashi, Tsukuba 305-8565, Japan.
ACS Appl Mater Interfaces. 2017 Jul 19;9(28):23918-23925. doi: 10.1021/acsami.7b04450. Epub 2017 Jul 5.
The bulk band structures of a variety of artificially constructed van der Waals chalcogenide heterostructures IVTe/VVI (IV: C, Si, Ge, Sn, Pb; V: As, Sb, Bi; VI: S, Se, Te) have been systematically examined using ab initio simulations based on density functional theory. The crystal structure and the electronic band structure of the heterostructures were found to strongly depend on the choice of elements as well as the presence of van der Waals corrections. Furthermore, it was found that the use of the modified Becke-Johnson local density approximation functional demonstrated that a Dirac cone is formed when tensile stress is applied to a GeTe/SbTe heterostructure, and the band gap can be controlled by tuning the stress. Based on these simulation results, a novel electrical switching device using a chalcogenide heterostructure is proposed.
使用基于密度泛函理论的第一性原理模拟，系统地研究了各种人工构建的范德华族碲化物异质结构 IVTe/VVI（IV：C、Si、Ge、Sn、Pb；V：As、Sb、Bi；VI：S、Se、Te）的体带结构。发现异质结构的晶体结构和电子能带结构强烈依赖于元素的选择以及范德华修正的存在。此外，还发现使用修正的 Becke-Johnson 局域密度近似泛函表明，当对 GeTe/SbTe 异质结构施加拉伸应力时会形成狄拉克锥，并且可以通过调节应力来控制能带隙。基于这些模拟结果，提出了一种使用硫族化物异质结构的新型电开关器件。
