Evidence of topological surface state in three-dimensional Dirac semimetal Cd3As2.
Evidence of topological surface state in three-dimensional Dirac semimetal Cd3As2.
复制标题
三维狄拉克半金属 Cd3As2 拓扑表面态的证据
DOI：
10.1038/srep06106
复制
发表时间：
2014-08-20
影响因子：
4.6
通讯作者：
Zhou XJ
中科院分区：
文献类型：
--
作者：
Yi H;Wang Z;Chen C;Shi Y;Feng Y;Liang A;Xie Z;He S;He J;Peng Y;Liu X;Liu Y;Zhao L;Liu G;Dong X;Zhang J;Nakatake M;Arita M;Shimada K;Namatame H;Taniguchi M;Xu Z;Chen C;Dai X;Fang Z;Zhou XJ
三维拓扑半金属代表了物质的一种新的量子态。不同于拓扑绝缘体中的表面态在二维动量平面中表现出线性色散，三维半金属的主体能带沿沿着所有方向线性色散。三维Weyl/Dirac半金属除了具有体材料中的无隙点外，还具有表面费米弧的“拓扑保护”表面态。虽然Cd 3As 2被认为是狄拉克半金属的一个可行的候选者，但还需要更多的研究来确定它的性质。特别是，拓扑表面状态，三维半金属的标志，尚未观察到在Cd 3As 2。本文报道了用角分辨光电子能谱方法测量Cd_3As_2（112）晶体表面的电子结构，并详细计算了能带结构.测量的费米面和能带结构显示出良好的协议与带结构计算与两个散装狄拉克带接近费米能级和形成狄拉克点附近的布里渊区中心。此外，首次发现了线性色散接近费米能级的拓扑表面态。这些结果提供了实验的性质上的拓扑非平凡的三维狄拉克锥Cd 3As 2。
The three-dimensional topological semimetals represent a new quantum state of matter. Distinct from the surface state in the topological insulators that exhibits linear dispersion in two-dimensional momentum plane, the three-dimensional semimetals host bulk band dispersions linearly along all directions. In addition to the gapless points in the bulk, the three-dimensional Weyl/Dirac semimetals are also characterized by “topologically protected” surface state with Fermi arcs on their surface. While Cd3As2is proposed to be a viable candidate of a Dirac semimetal, more investigations are necessary to pin down its nature. In particular, the topological surface state, the hallmark of the three-dimensional semimetal, has not been observed in Cd3As2. Here we report the electronic structure of Cd3As2investigated by angle-resolved photoemission measurements on the (112) crystal surface and detailed band structure calculations. The measured Fermi surface and band structure show a good agreement with the band structure calculations with two bulk Dirac-like bands approaching the Fermi level and forming Dirac points near the Brillouin zone center. Moreover, the topological surface state with a linear dispersion approaching the Fermi level is identified for the first time. These results provide experimental indications on the nature of topologically non-trivial three-dimensional Dirac cones in Cd3As2.
登录
查看更多内容
角分辨光电发射光谱揭示 SrMnBi2 和 CaMnBi2 中狄拉克锥体的强各向异性
影响因子：
4.6
作者：
Feng Y;Wang Z;Chen C;Shi Y;Xie Z;Yi H;Liang A;He S;He J;Peng Y;Liu X;Liu Y;Zhao L;Liu G;Dong X;Zhang J;Chen C;Xu Z;Dai X;Fang Z;Zhou XJ
通讯作者：
Zhou XJ
影响因子：
3.7
作者：
Wang, Zhijun;Sun, Yan;Fang, Zhong
通讯作者：
Fang, Zhong
影响因子：
8.6
作者：
Borisenko, Sergey;Gibson, Quinn;Cava, Robert J.
通讯作者：
Cava, Robert J.
影响因子：
2.1
作者：
JAYGERIN, JP;AUBIN, MJ;CARON, LG
通讯作者：
CARON, LG
稳定的三维拓扑狄拉克半金属Cd3As2
影响因子：
41.2
作者：
Liu, Z. K.;Jiang, J.;Chen, Y. L.
通讯作者：
Chen, Y. L.