论文标题
对二维和批量材料的电子 - 音波耦合和迁移率的远程静电贡献
Long-range electrostatic contribution to the electron-phonon couplings and mobilities of two-dimensional and bulk materials
论文作者
论文摘要
电荷运输在二维材料的多种潜在应用中起着至关重要的作用,包括现场效应晶体管,太阳能电池和透明导体。在大多数工作温度下,通过晶格振动散射载体会阻碍电荷传输。因此,评估固有的声子受限载体迁移率对于确定有前途的下一代设备的候选人至关重要。在这里,我们提供了一个框架,以通过依靠傅立叶挡板插值来有效地通过玻璃体传输方程来计算二维材料的漂移和霍尔载体迁移率。建立在最近对动态矩阵和声子分散的长期贡献的基础上[Phys。 Rev. X 11,041027(2021)],我们将方法扩展到电子 - 音波耦合,包括动态偶极子和四翼型的效果。我们确定了与浆果联系相关的前所未有的贡献,这对于保留该理论的陷入僵局的协方差至关重要。这种贡献不是针对2D晶体的特异性,而是涉及3D情况,因为我们通过应用于批量SRO证明。我们展示了从SNS2到MOS2,石墨烯,BN,INSE和磷烯的多种相关单层选择的方法。我们还发现了INSE中霍尔孔迁移率的非平凡温度演变,因此,由于INSE价带的墨西哥帽电子结构,迁移率随温度高于150 K的温度而增加。总体而言,我们发现动态四极是必不可少的,并且可能影响超过75%的载流子。
Charge transport plays a crucial role in manifold potential applications of two-dimensional materials, including field effect transistors, solar cells, and transparent conductors. At most operating temperatures, charge transport is hindered by scattering of carriers by lattice vibrations. Assessing the intrinsic phonon-limited carrier mobility is thus of paramount importance to identify promising candidates for next-generation devices. Here we provide a framework to efficiently compute the drift and Hall carrier mobility of two-dimensional materials through the Boltzmann transport equation by relying on a Fourier-Wannier interpolation. Building on a recent formulation of long-range contributions to dynamical matrices and phonon dispersions [Phys. Rev. X 11, 041027 (2021)], we extend the approach to electron-phonon coupling including the effect of dynamical dipoles and quadrupoles. We identify an unprecedented contribution associated with the Berry connection that is crucial to preserve the Wannier-gauge covariance of the theory. This contribution is not specific to 2D crystals, but also concerns the 3D case, as we demonstrate via an application to bulk SrO. We showcase our method on a wide selection of relevant monolayers ranging from SnS2 to MoS2, graphene, BN, InSe, and phosphorene. We also discover a non-trivial temperature evolution of the Hall hole mobility in InSe whereby the mobility increases with temperature above 150 K due to the mexican-hat electronic structure of the InSe valence bands. Overall, we find that dynamical quadrupoles are essential and can impact the carrier mobility in excess of 75%.