Luo Ying, Zhao Guojun, Wang Shudong
School of Physical Science and Technology, Inner Mongolia University, Hohhot, 010021, China.
Phys Chem Chem Phys. 2020 Mar 11;22(10):5688-5692. doi: 10.1039/c9cp06945c.
Through first-principles calculations, the electron-phonon scattering of two-dimensional monolayer AsSb is investigated. The Boltzmann transport equation is used to compute the phonon limited carrier mobility. We find that the optical phonon scattering rates are much larger than acoustic ones around the valence band maximum (VBM) and the conduction band minimum (CBM). The phonon-decomposed scattering results show that transverse optical (TO) phonon modes dominate the scattering around VBM, while longitudinal and out-of-plane acoustic modes contribute mostly to the scattering at higher energy. TO phonon modes dominate the scattering for electrons over all energy level, and the electron-phonon matrix element analysis verified the results. Finally, we observed that the largest mean free paths for hot holes and hot electrons are 20 nm and 8 nm, respectively. That is the best range to extract the hot holes and hot electrons. More interestingly, owing to the in-pane net dipole moment of AsSb, the intrinsic electron/hole mobility of AsSb are 38/50 cm2 V-1 s-1, which are less than monolayer arsenene and antimonene.
通过第一性原理计算，研究了二维单层砷化锑的电子 - 声子散射。采用玻尔兹曼输运方程计算声子限制的载流子迁移率。我们发现，在价带顶（VBM）和导带底（CBM）附近，光学声子散射率远大于声学声子散射率。声子分解散射结果表明，横向光学（TO）声子模式在VBM附近的散射中占主导地位，而纵向和面外声学模式在较高能量下的散射中贡献最大。TO声子模式在所有能级上对电子散射起主导作用，电子 - 声子矩阵元分析验证了该结果。最后，我们观察到热空穴和热电子的最大平均自由程分别为20 nm和8 nm。这是提取热空穴和热电子的最佳范围。更有趣的是，由于砷化锑的面内净偶极矩，其本征电子/空穴迁移率为38/50 cm2 V-1 s-1，小于单层砷烯和锑烯。
