论文标题
基于二维离子材料中的简化$ p $ - 欧洲的现实平坦型号
Realistic flat-band model based on degenerate $p$-orbitals in two-dimensional ionic materials
论文作者
论文摘要
尽管已经提出了几种理论模型来设计电子平坦带，但仍缺乏二维原子晶体中的明确实验实现。在这里，我们提出了一种基于二维离子材料中的三倍变性$ p $ - 轨道的新颖且现实的平坦模型。我们的理论分析和第一原理的计算表明，拟议的平流频带可以在碱金属葡萄糖层和金属碳群化合物的1T分层材料中实现。从理论上讲，一些前者被预测为稳定为分层材料（例如K $ _2 $ s），而后者的某些材料已在以前的作品中实验化（例如，GD $ _2 $ _2 $ CCL $ _2 $）。更有趣的是，平面部分在k $ _2 $ s单层和石墨烯层的异质结构中部分填充。旋转极化的几乎平面频段可以在GD $ _2 $ _2 $ ccl $ _2 $单层的铁磁状态下实现，该状态已在实验中制造。我们的理论模型以及材料预测为研究平坦带和相关外来量子阶段的研究提供了现实的平台。
Though several theoretical models have been proposed to design electronic flat-bands, the definite experimental realization in two-dimensional atomic crystal is still lacking. Here we propose a novel and realistic flat-band model based on threefold degenerate $p$-orbitals in two-dimensional ionic materials. Our theoretical analysis and first-principles calculations show that the proposed flat-band can be realized in 1T layered materials of alkali-metal chalogenides and metal-carbon group compounds. Some of the former are theoretically predicted to be stable as layered materials (e.g., K$_2$S), and some of the latter have been experimentally fabricated in previous works (e.g., Gd$_2$CCl$_2$). More interestingly, the flat-band is partially filled in the heterostructure of a K$_2$S monolayer and graphene layers. The spin polarized nearly flat-band can be realized in the ferromagnetic state of a Gd$_2$CCl$_2$ monolayer, which has been fabricated in experiments. Our theoretical model together with the material predictions provide a realistic platform for the study of flat-bands and related exotic quantum phases.
