Texas Materials Institute and Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
Phys Rev Lett. 2023 Feb 24;130(8):087001. doi: 10.1103/PhysRevLett.130.087001.
Two-dimensional semiconductors have demonstrated great potential for next-generation electronics and optoelectronics, however, the current 2D semiconductors suffer from intrinsically low carrier mobility at room temperature, which significantly limits their applications. Here we discover a variety of new 2D semiconductors with mobility 1 order of magnitude higher than the current ones and even higher than bulk silicon. The discovery was made by developing effective descriptors for computational screening of the 2D materials database, followed by high-throughput accurate calculation of the mobility using a state-of-the-art first-principles method that includes quadrupole scattering. The exceptional mobilities are explained by several basic physical features; particularly, we find a new feature: carrier-lattice distance, which is easy to calculate and correlates well with mobility. Our Letter opens up new materials for high performance device performance and/or exotic physics, and improves the understanding of the carrier transport mechanism.
二维半导体在下一代电子学和光电子学方面具有巨大的潜力，然而，目前的二维半导体在室温下的载流子迁移率较低，这极大地限制了它们的应用。在这里，我们发现了多种新的二维半导体，其迁移率比目前的二维半导体高一个数量级，甚至比体硅还高。这一发现是通过开发有效的二维材料数据库计算筛选描述符，并使用包括四极散射在内的最先进的第一性原理方法进行高通量精确迁移率计算来实现的。这些异常高的迁移率可以用几个基本的物理特性来解释；特别是，我们发现了一个新的特征：载流子-晶格距离，这个特征很容易计算，并且与迁移率有很好的相关性。我们的研究结果为高性能器件性能和/或奇异物理开辟了新的材料，同时也提高了对载流子输运机制的理解。
