论文标题
超导性与插入式bi $ _2 $ se $ _3 $的LIFSHITZ过渡之间的链接
Link between superconductivity and a Lifshitz transition in intercalated Bi$_2$Se$_3$
论文作者
论文摘要
拓扑超导性是一个外来的物质阶段，其中完全损失的超导散装构成了受拓扑保护的无间隙主要表面状态。拓扑绝缘子BI $ _2 $ SE $ _3 $之间铜，锶或niobium的插入量增加了载体密度并导致超导性，建议是拓扑。在这里，我们使用角度分辨光发射光谱（ARPES）和Shubnikov-de Haas（SDH）振荡研究了跨嵌入BI $ _2 $ SE $ _3 $的电子结构。尽管显而易见的低大厅数量为$ \ sim2 \ times 10 ^{19} $ cm $ $ ^{ - 3} $，但我们表明，费米表面形状为开放式圆柱体，其较大的载体密度为$ \ sim 10 ^{20} $ cm $ $ cm $ ^{ - 3} $。我们建议，插入的BI $ _2 $ SE $ _3 $中的超导率随着准2D开放式费米表面的外观而出现。
Topological superconductivity is an exotic phase of matter in which the fully gapped superconducting bulk hosts gapless Majorana surface states protected by topology. Intercalation of copper, strontium or niobium between the quintuple layers of the topological insulator Bi$_2$Se$_3$ increases the carrier density and leads to superconductivity that is suggested to be topological. Here we study the electronic structure of strontium-intercalated Bi$_2$Se$_3$ using angle resolved photoemission spectroscopy (ARPES) and Shubnikov-de Haas (SdH) oscillations. Despite the apparent low Hall number of $\sim2 \times 10 ^{19}$cm$^{-3}$, we show that the Fermi surface is shaped as an open cylinder with a larger carrier density of $\sim 10 ^{20}$cm$^{-3}$. We suggest that superconductivity in intercalated Bi$_2$Se$_3$ emerges with the appearance of a quasi-2D open Fermi surface.
