标题： 超导铜插层的Bi$_2$Se$_3$内部压力 显示英文标题

标题： Internal pressure in superconducting Cu intercalated Bi$_2$Se$_3$

摘要： 角分辨光电子能谱用于研究超导电化学插层 Cu$_x$Bi$_2$Se$_3$的能带结构。 我们发现，在这些样品中，$\Gamma$点的能隙比原始 Bi$_2$Se$_3$中的大得多。 与能带结构计算结果的比较表明，这个大能隙的起因是由于 Cu 插层引起的无序所产生的内部应力。 我们建议内部压力可能对于Cu$_x$Bi$_2$Se$_3$的超导性是必要的。 显示英文摘要

摘要： Angle-resolved photoemission spectroscopy is used to study the band-structure of superconducting electrochemically intercalated Cu$_x$Bi$_2$Se$_3$. We find that in these samples the band-gap at the $\Gamma$ point is much larger than in pristine Bi$_2$Se$_3$. Comparison to the results of band-structure calculations indicates that the origin of this large gap is internal stress caused by disorder created by the Cu intercalation. We suggest that the internal pressure may be necessary for superconductivity in Cu$_x$Bi$_2$Se$_3$.