论文标题
$ \ mathrm {sr} _ {1-y} \ Mathrm {ca} _ {y} \ Mathrm {fe_ {2}}（\ Mathrm {as} _ {as} _ {1-x}} \ Mathrm {p} $ MATHRM {P} $ MATHRM { 0.25，$ y $ = 0.08）通过角度分辨光发射光谱揭示
Electronic Structure of $\mathrm{Sr}_{1-y}\mathrm{Ca}_{y}\mathrm{Fe_{2}}(\mathrm{As}_{1-x}\mathrm{P}_{x}\mathrm{)_{2}}$ ($x$ = 0.25, $y$ = 0.08) Revealed by Angle-Resolved Photoemission Spectroscopy
论文作者
论文摘要
我们已经研究了$ \ mathrm {sr} _ {1-y} \ Mathrm {ca} _ {y} \ Mathrm {fe_ {2}}（\ Mathrm {as} _ {1-x}} _ {1- X} \ MATHRM {p} _ARTRM， （$ x $ = 0.25，$ y $ = 0.08）通过角度分辨光发射光谱法。从与$ \ mathrm {bafe_ {2}}（\ Mathrm {as} _ {1-x} \ Mathrm {p} _ {x} \ Mathrm {）_ {2}} $的结果相比，讨论结构。观察到的FSS具有三个维度形状。 $γ$和$ z $点之间的一个孔FSS强烈扭曲，并且在$ z $点上观察到的最内向的FS消失在$γ$点上，这与FS的功能相似$ \ MATHRM {SRFE_ {2}}（\ Mathrm {as} _ {1-x} \ MathRM {p} _ {X} \ Mathrm {）_ {2}}}} $（$ x $ = 0.35）。在超导状态下，$ d_ {xy} $ electron FS附近的$ d_ {xy} $ electon的节点（如$ x $点）存在，而其他高对称点周围的间隙则是各向异性的。检查了基于自旋和/或轨道波动的几种理论模型，以解释所有这些实验结果。
We have investigated the electronic structure of $\mathrm{Sr}_{1-y}\mathrm{Ca}_{y}\mathrm{Fe_{2}}(\mathrm{As}_{1-x}\mathrm{P}_{x}\mathrm{)_{2}}$ ($x$ = 0.25, $y$ = 0.08) by means of angle-resolved photoemission spectroscopy. From the comparison with the results of $\mathrm{BaFe_{2}}(\mathrm{As}_{1-x}\mathrm{P}_{x}\mathrm{)_{2}}$, the effects of smaller structural anisotropy ($c/a$) on the Fermi surfaces (FSs) and the gap structures are discussed. The observed FSs have three dimensional shapes. One of the hole FSs is strongly warped between the $Γ$ and $Z$ points, and the innermost FS observed at the $Z$ point disappears at the $Γ$ point, which is similar to the FS features of $\mathrm{SrFe_{2}}(\mathrm{As}_{1-x}\mathrm{P}_{x}\mathrm{)_{2}}$ ($x$ = 0.35). In the superconducting state, the node like gap-minimum is present for the $d_{xy}$ electron FS near the $X$ point, while the gaps around the other high symmetry points are isotropic. Several theoretical models based on the spin and/or the orbital fluctuation are examined to explain all these experimental results.
