arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1408.6310cond-mat.mes-hallcond-mat.mtrl-sci
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蓝磷中的狄拉克费米子

Dirac Fermions in Blue-Phosphorus

Yuanchang Li, Xiaobin Chen

摘要:

我们提出了在磷烯中可以设计出具有四配位磷原子的狄拉克锥。关键是通过$sp^2$组态在能量上分离面内轨道($s$、$p_x$和$p_y$)和面外轨道($p_z$),产生相应的$σ$和$π$特征狄拉克锥,然后淬灭后者。作为原理验证的研究,我们实现了$σ$ -字符狄拉克锥在氢化/氟化磷与蜂窝晶格。所得到的狄拉克锥位于$K$点,具有轻微的各向异性,沿$Γ$ K/KM方向的费米速度分别为石墨烯的0.91/1.23倍,并且对空穴保持良好的线性,直到$\sim$ 2 eV. $σ$型狄拉克锥的一个实质性优点是可以方便地通过面内应变调节狄拉克能隙。我们的研究结果为基于Dirac材料的高性能电子器件的开发铺平了新的道路。

英文摘要:

We propose that Dirac cones can be engineered in phosphorene with fourfold-coordinated phosphorus atom. The key is to separate in energy the in-plane ($s$, $p_x$ and $p_y$) and out-of-plane ($p_z$) oribtals through the $sp^2$ configuration, yielding respective $σ$- and $π$-character Dirac cones, and then quench the latter. As a proof-of-principle study, we realize $σ$-character Dirac cone in hydrogenated/fluorinated phosphorene with the honeycomb lattice. The obtained Dirac cones are at $K$-points, slightly anisotropic, with Fermi velocities of 0.91/1.23 times that of graphene along $Γ$K/KM direction, and maintain a good linearity up to $\sim$2 eV for holes. One substantive advantage of $σ$-character Dirac cone is its convenience to tune the Dirac gap via in-plane strain. Our findings pave a new way for development of high performance electronic devices based on Dirac materials.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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