Vu Tuan V, Linh Tran P T, Phuc Huynh V, Duque C A, Kartamyshev A I, Hieu Nguyen N
Division of Computational Physics, Institute for Computational Science, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam.
Faculty of Electrical & Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City 700000, Vietnam.
J Phys Condens Matter. 2021 Nov 4;34(4). doi: 10.1088/1361-648X/ac316e.
Two-dimensional Janus monolayers have outstanding electronic and transport properties due to their asymmetric atomic structures. In the present work, we systematically study the structural, electronic, and transport properties of the Janus GaIn(= S, Se, Te) monolayers by using the first-principles calculations. The stability of the investigated monolayers is confirmed via the analysis of vibrational spectrum and molecular dynamics simulations. Our calculations demonstrate that while GaInSand GaInSemonolayers are direct semiconductors, GaInTemonolayer exhibits the characteristics of an indirect semiconductor. The band gap of GaIndecreases when the chalcogen elementvaries from S to Te. Obtained results reveal that small spin-orbit splitting energy in the valence band is found around the Γ point of the Brillouin zone when the spin-orbit coupling is included. Interestingly, GaInSand GaInSehave high and directional isotropic electron mobility meanwhile the directional anisotropy of the electron mobility is found in the Janus GaInTemonolayer. Our findings not only present superior physical properties of GaInmonolayers but also show promising potential applications of these materials in nanoelectronic devices.
二维Janus单分子层由于其不对称的原子结构而具有出色的电子和输运特性。在本工作中，我们通过第一性原理计算系统地研究了Janus GaIn(= S, Se, Te)单分子层的结构、电子和输运特性。通过振动光谱分析和分子动力学模拟证实了所研究单分子层的稳定性。我们的计算表明，虽然GaInS和GaInSe单分子层是直接半导体，但GaInTe单分子层表现出间接半导体的特性。当硫族元素从S变化到Te时，GaIn的带隙减小。所得结果表明，当包含自旋轨道耦合时，在布里渊区的Γ点附近价带中发现了小的自旋轨道分裂能。有趣的是，GaInS和GaInSe具有高且各向同性的电子迁移率，而在Janus GaInTe单分子层中发现了电子迁移率的方向各向异性。我们的发现不仅展示了GaIn单分子层优异的物理性质，还表明了这些材料在纳米电子器件中具有广阔的潜在应用前景。
