论文标题
通过应变工程增强了各向异性2D四核的载体迁移率
Enhanced carrier mobility in anisotropic 2D tetrahex-carbon through strain engineering
论文作者
论文摘要
最近预测的二维（2D）碳同素同素（由四方和六边形环组成的四碳碳）由于其独特的机械和电子性能而引起了研究兴趣。 Tetrahex-C显示了超高强度，负泊松比，直接带隙和高载体迁移率。在这项工作中，我们采用第一原理密度功能理论计算来探索电子特性（例如载体有效质量和tetrahex-C中的迁移率）的定向依赖性。 Tetrahex-C在有效的电荷载体中表现出强大的各向异性，因此其迁移率（电导）表现出强烈的取向偏好。更有趣的是，我们发现这种独特的各向异性载体有效质量和迁移率可以通过简单的单轴菌株来控制。有效质量的方向依赖性可以通过在孔（电子）的扶手椅方向上施加〜7％（11％）的单轴拉伸应变来显着旋转90度。结果，四面体C中的固有载流子迁移率显着增强。该结果可用于在Tetrahex-C中的潜在电子和机械应用。
A recently predicted two dimensional (2D) carbon allotrope, tetrahex-carbon consisting of tetragonal and hexagonal rings, draws research interests due to its unique mechanical and electronic properties. Tetrahex-C shows ultrahigh strength, negative Poisson ratio, a direct band gap and high carrier mobility. In this work, we employ first-principles density-functional theory calculations to explore the directional dependence of electronic properties such as carrier effective mass and mobility in tetrahex-C. Tetrahex-C demonstrates strong anisotropicity in effective mass of charge carrier and therefore its mobility (electric conductance) exhibits a strong orientation preference. More interesting, we find that such unique anisotropic carrier effective mass and mobility can be controlled by simple uniaxial strain. The orientation dependence of effective mass can be dramatically rotated by 90 degrees through applying uniaxial tensile strain beyond ~ 7% (11%) in the armchair direction for the hole (electron). As a result, the intrinsic carrier mobility in tetrahex-C is significantly enhanced. The results are useful for potential electronic and mechanical applications in tetrahex-C.
