论文标题
二维稀有珍珠2 $ \ textit {h} $ - gd $ \ textit {xy} $（$ \ textit {x} $，$ \ textit {y} $ = cl，br，br，i，i，$ \ textit {x} $ \ textit {x} $ \ neq $ \ neq $ \ neq $ \ textit \ textit \ y}高居里温度和大山谷极化
Two-dimensional rare-earth Janus 2$\textit{H}$-Gd$\textit{XY}$ ($\textit{X}$,$\textit{Y}$=Cl, Br, I, $\textit{X}$$\neq$$\textit{Y}$) monolayers: Bipolar ferro-magnetic semiconductors with high Curie temperature and large valley polarization
论文作者
论文摘要
二维（2D）铁磁半导体由于潜在的纳米级电子设备的应用而表现出极大的兴趣。在这项工作中，Janus 2 $ h $ -gd $ xy $（$ x $，$ y $ = cl，br，i，$ x $ x $ x $ \ neq $$ y $）具有稀有元素GD（4 $ f^{7} $+5 $+5 $+5 $ d^{1} $）的单层。对于Janus 2 $ h $ -gd $ xy $单层，可以确认小于0.25 j/m $^{2} $和出色的动力/热稳定性，这表现出双极磁性半导体特征，具有高于260 k的高质量和大型的旋转效果，并可以进一步转化为阶段，并且可以进一步转化，并在阶段变化。 （5-6 \％）。此外，可以在2 $ h $ -GDICL和2 $ h $ -gdibr单层中观察到平面磁各向异性。相反，2 $ h $ -GDBRCL单层展示了垂直磁各向异性角色，该角色源自GD-$ p $/$ d $和卤素原子-P $ orbitals之间的竞争。 Janus 2 $ h $ -gd $ xy $单层的计算谷光学动作展示了杰出的山谷选择性圆形二色性，预计该二色性将实现偏光灯的特殊山谷激发。 VALLEY-ZEEMAN在Valance Band中的自发山谷效应Janus 2 $ h $ -gd $ xy $单层会引起60-120 MEV的巨大山谷拆分，这也对各种外部双轴菌株也很强大。 Janus 2 $ H $ -GD $ XY $ Systems在编码和处理信息非常必要的可调谷自由度。
Two-dimensional (2D) ferromagnetic semiconductors show great interest due to their potential applications for the nanoscale electronic devices. In this work, the Janus 2$H$-Gd$XY$ ($X$, $Y$=Cl, Br, I, $X$$\neq$$Y$) monolayers with rare-earth element Gd (4$f^{7}$+5$d^{1}$) are predicted by the first-principles calculations. Small exfoliation energy of less than 0.25 J/m$^{2}$ and excellent dynamical/thermal stabilities can be confirmed for the Janus 2$H$-Gd$XY$ monolayers, which exhibit the bipolar magnetic semiconductor character with high Curie temperatures above 260 K and large spin-orbit coupling effect, and can be further transformed into the half-semiconductor phase under proper tensile strains (5-6\%). In addition, the in-plane magnetic anisotropy can be observed in the 2$H$-GdICl and 2$H$-GdIBr monolayers. On the contrary, the 2$H$-GdBrCl monolayer exhibits perpendicular magnetic anisotropy character, which originates from the competition between Gd-$p$/$d$ and halogen atom-$p$ orbitals. Calculated valley optical actions of the Janus 2$H$-Gd$XY$ monolayers exhibit distinguished valley-selective circular dichroisms, which is expected to realize the special valley excitation by polarized light. Spontaneously valley-Zeeman effect in the valance band for the Janus 2$H$-Gd$XY$ monolayers induces a giant valley splitting of 60-120 meV, which is also robust against various external biaxial strains. Tunable valley degree of freedom in the Janus 2$H$-Gd$XY$ systems is very necessary for encoding and processing information.
