标题： 低温下近邻相互作用存在的$n$型单层过渡金属硫族化合物的纵向和横向迁移率 显示英文标题

标题： Longitudinal and transverse mobilities of $n$-type monolayer transition metal dichalcogenides in the presence of proximity-induced interactions at low temperature

摘要： 我们详细研究了在低温下，邻近诱导相互作用（如Rashba自旋轨道耦合RSOC和交换相互作用）对$n$型单层过渡金属二硫属化物（TMDs）电子输运性质的影响。通过求解包含$\mathbf{k}\cdot\mathbf{p}$汉密尔顿量的薛定谔方程计算了电子能带结构，并用标准的随机相位近似方法评估了由电子-电子相互作用引起的电屏蔽效应。特别是，利用从半经典玻尔兹曼方程推导出的动量平衡方程，计算了纵向和横向霍尔迁移率，在此过程中考虑了低温下电子与杂质相互作用为主要散射中心。所得结果表明，RSOC可以在不同谷中的自旋分裂子带中诱导面内自旋分量，而交换相互作用可以消除不同谷中电子的能量简并性。两个谷中的Berry曲率符号相反，这会在谷电子上引入相反方向的洛伦兹力。因此，非简并谷的横向电流不再被抵消，从而可以观察到横向电流或霍尔迁移率。有趣的是，我们发现，在固定的有效Zeeman场的情况下，通过改变Rashba参数，可以将单层TMDs中的最低自旋分裂传导子带从$K'$谷调整到$K$谷。不同谷中电子的占据也随着载流子密度的变化而变化。因此，我们可以通过改变Rashba参数、有效Zeeman场和载流子密度（例如通过铁磁基底的存在和/或施加栅极电压）来改变霍尔电流的大小和方向。 显示英文摘要

摘要： We present a detailed theoretical investigation on the electronic transport properties of $n$-type monolayer (ML) transition metal dichalcogenides (TMDs) at low temperature in the presence of proximity-induced interactions such as Rashba spin-orbit coupling (RSOC) and the exchange interaction. The electronic band structure is calculated by solving the Schr\"{o}dinger equation with a $\mathbf{k}\cdot\mathbf{p}$ Hamiltonian, and the electric screening induced by electron-electron interaction is evaluated under a standard random phase approximation approach. In particular, the longitudinal and transverse or Hall mobilities are calculated by using a momentum-balance equation derived from a semi-classical Boltzmann equation, where the electron-impurity interaction is considered as the principal scattering center at low temperature. The obtained results show that the RSOC can induce the in-plane spin components for spin-split subbands in different valleys, while the exchange interaction can lift the energy degeneracy for electrons in different valleys. The opposite signs of Berry curvatures in the two valleys would introduce opposite directions of Lorentz force on valley electrons. As a result, the transverse currents from nondegenerate valleys can no longer be canceled out so that the transverse current or Hall mobility can be observed. Interestingly, we find that at a fixed effective Zeeman field, the lowest spin-split conduction subband in ML-TMDs can be tuned from one in the $K'$-valley to one in the $K$-valley by varying the Rashba parameter. The occupation of electrons in different valleys also varies with changing carrier density. Therefore, we can change the magnitude and direction of the Hall current by varying the Rashba parameter, effective Zeeman field, and carrier density by, e.g., the presence of a ferromagnetic substrate and/or applying a gate voltage.