标题： 临近交换相互作用和外部电场存在时单层过渡金属二硫属化物的磁光电导 显示英文标题

标题： Magneto-optical conductivity of monolayer transition metal dichalcogenides in the presence of proximity-induced exchange interaction and external electrical field

摘要： 我们理论研究了单层（ML）过渡金属二硫属化物（TMDs）在外加电场和量子化磁场以及由邻近诱导交换相互作用存在下的磁光（MO）性质。通过求解薛定谔方程研究了相应的朗道能级（LL）结构，并评估了外加磁场下单层TMDs中的自旋极化。考察了三角畸变对朗道能级和磁光吸收的影响。此外，利用标准的随机相位近似（RPA）结合 Kubo 公式，通过动态介电函数计算纵向磁光电导率。我们以单层 MoS$_2$为例，检验了邻近诱导交换相互作用、外加电场和磁场对朗道能级间电子跃迁引起的磁光电导率的影响。对于导带或价带内的电子跃迁，在太赫兹（THz）频段可以观察到两个吸收峰；而导带和价带朗道能级间的电子跃迁在可见光范围内显示出一系列吸收峰。我们发现，邻近诱导交换相互作用、载流子密度以及外加电场和磁场的强度能够有效调节吸收峰的位置和磁光吸收光谱的形状。本研究的结果有助于深入理解单层 TMDs 的磁光性质，这些性质可能被应用于工作在可见光到太赫兹频段的磁光、自旋电子和能谷电子器件。 显示英文摘要

摘要： We theoretically investigate the magneto-optical (MO) properties of monolayer (ML) transition metal dichalcogenides (TMDs) in the presence of external electrical and quantizing magnetic fields and of the proximity-induced exchange interaction. The corresponding Landau Level (LL) structure is studied by solving the Schr\"odinger equation and the spin polarization in ML-TMDs under the action of the magnetic field is evaluated.The impact of trigonal warping on LLs and MO absorption is examined. Furthermore, the longitudinal MO conductivity is calculated through the dynamical dielectric function under the standard random-phase approximation (RPA) with the Kubo formula. We take ML-MoS$_2$ as an example to examine the effects of proximity-induced exchange interaction, external electrical and magnetic fields on the MO conductivity induced via intra- and interband electronic transitions among the LLs. For intraband electronic transitions within the conduction or valence bands, we can observe two absorption peaks in terahertz (THz) frequency range. While the interband electronic transitions between conduction and valence LLs show a series of absorption peaks in the visible range. We find that the proximity-induced exchange interaction, the carrier density, the strengths of the external electrical and magnetic fields can effectively modulate the positions of the absorption peaks and the shapes of the MO absorption spectra. The results obtained from this study can benefit to an in-depth understanding of the MO properties of ML-TMDs which can be potentially applied for magneto-optic, spintronic and valleytronic devices working in visible to THz frequency bandwidths.