２次元物質ゲルマネンの実デバイス環境下における電子状態・輸送特性の理論研究

石墨烯的缺点促使科学家们研究石墨烯以外的新型二维材料。日耳曼烯和stanene具有狄拉克锥、超高载流子迁移率和量子自旋霍尔效应（QSHE）等令人着迷的特性。虽然在实验中已经在几种底物上合成了它们，但仍然缺乏合适的底物来保留吸引的狄拉克锥和QSHE。通过将DFT与材料信息学相结合，我们从数据库中超过185,000个条目中找到了锗烯和stanene的几种合适的底物。我们的模型分析表明，基材与目标材料之间的相互作用相当于伪电场。（Physical Review B, 96, 075427）此外，我们正在实施一种机器学习方法，以提供准确和快速的二维材料沉积过程模拟。除了原计划外，我们还将目光投向了过渡金属二硫族（TMDs）成员WTe2。由于奇异的不饱和磁阻（MR）和可能的ii型Weyl锥，它已成为二维材料中的一颗新星。然而，对WTe2的表面弛豫和表面电子结构的研究还很缺乏，特别是对少层板的研究。为了解决这些问题，我们研究了WTe2中精确的表面弛豫和机械可调谐的电子结构（Applied Physics Express, 10,045702; ACS Nano, 11,11459）。在WTe2中发现机械可调表面偶极子的研究正在进行中。

The drawbacks of graphene stimulate scientists to investigate novel 2D materials beyond graphene. Germanene and stanene have various fascinating properties, such as the Dirac-cone, ultrahigh carrier mobility, and the quantum spin Hall effect (QSHE). While they have been synthesized on several substrates in experiment, there is still a lack of suitable substrates to preserve the attractive Dirac-cone and QSHE. By combining DFT with materials informatics, we have found several suitable substrates for germanene and stanene from more than 185, 000 entries in the database. The interaction between the substrate and the target 2D materials is equivalent to pseudoelectric field, as revealed by our model analysis. (Physical Review B, 96, 075427) Furthermore, we are implementing a machine learning approach to provide accurate and fast simulation of the deposition procedure of 2D materials.In addition to the original plan, we also put our eyes on WTe2, a member of transition metal dichalcogenides (TMDs) family. It has been a rising star in 2D materials due to the exotic non-saturating magnetoresistance (MR) and the possible type-II Weyl cone. However, the study about the surface relaxation and surface electronic structure is insufficient in WTe2, especially for few layer slabs. To solve the problems, we have investigated the accurate surface relaxation and mechanically tunable electronic structure in few-layer WTe2 (Applied Physics Express, 10, 045702; ACS Nano, 11, 11459). The research about the mechanically tunable surface dipole found in few-layer WTe2 is in preparation.