节点面晶体的拓扑特性

提出了实现节点面晶体的冷原子晶格方案, 讨论了节点面晶体的拓扑特性.通过调节激光参数, 系统可以实现3种不同相(拓扑节点面金属相, 拓扑平庸的金属相以及拓扑平庸的能带绝缘相)之间的相变.分别讨论了系统处于不同相态下，其节点面、能带、表面态和态密度的变化情况.结果表明:当系统处于节点面半金属相时, 晶体中存在拓扑保护的边缘流；而相变后系统为拓扑平庸态.通过研究不同晶面讨论了这种三维拓扑金属在不同截面的变化特性, 结合表面态和电子态密度, 可以更好地反映系统的拓扑特性.

Topological Properties of the Nodal Surface Crystal

A cold atomic lattice scheme of realizing the nodal surface crystal was proposed and its topological properties were investigated. By adjusting laser parameters, the system can reach three different phases, i.e., topological metallic phase, trivial metallic phase and band insulating phase. The relation among nodal surface, energy band, edge states and density of states in different phases were studied, and the results reveal that the topologically protected surface state can be found in the nodal surface crystal, i.e., the system shows the features of a topological metal.