论文标题
铁pnictides中的半金属旋转密度波状态
Semimetallic spin-density wave state in iron pnictides
论文作者
论文摘要
我们检查了铁pnictides铁中半金属旋转密度态的存在。在实验观察到的金属自旋密度波状态中，对称性保护的狄拉克锥远离费米表面，从而产生了微小的口袋，并且还有其他费米口袋，例如大约$γ$。我们发现，相对于费米表面的一对狄拉克点的位置对$ d_ {xz} $和$ d_ {yz} $ orbitals之间的轨道分裂表现出明显的敏感性。此外，在存在轨道分裂的情况下，可以抑制与狄拉克锥无关的费米口袋，以便可以实现半金属旋转密度波状态。我们用形成狄拉克锥的频带的斜率和轨道内容物的差异来解释这些发现，并获得取决于这两个和其他参数的必要条件，共存的狄拉克半金属和旋转密度波状态。此外，当沿着$ x $或$ y $ axes定向时，在色带几何形状中研究了拓扑保护的边缘状态。
We examine the existence of semimetallic spin-density wave states in iron pnictides. In the experimentally observed metallic spin-density wave state, the symmetry-protected Dirac cones are located away from the Fermi surface giving rise to tiny pockets and there are also additional Fermi pockets such as one around $Γ$. We find that the location of a pair of Dirac points with respect to the Fermi surface exhibits significant sensitivity to the orbital splitting between the $d_{xz}$ and $d_{yz}$ orbitals. Besides, in the presence of orbital splitting, the Fermi pockets not associated with the Dirac cones, can be suppressed so that a semimetallic spin-density wave state can be realized. We explain these finding in terms of difference in the slopes and orbital contents of the bands which form the Dirac cone, and obtain the necessary conditions dependent on these two and other parameters for the coexisting Dirac semimetallic and spin-density wave states. Additionally, the topologically protected edge states are studied in the ribbon geometry when the same are oriented either along $x$ or $y$ axes.
