School of Physics, Beijing Institute of Technology, Beijing 100081, China.
Phys Rev Lett. 2013 Aug 9;111(6):066804. doi: 10.1103/PhysRevLett.111.066804. Epub 2013 Aug 6.
We investigate the structure and physical properties of the undoped bilayer silicene through first-principles calculations and find the system is intrinsically metallic with sizable pocket Fermi surfaces. When realistic electron-electron interaction turns on, the system is identified as a chiral d+id' topological superconductor mediated by the strong spin fluctuation on the border of the antiferromagnetic spin density wave order. Moreover, the tunable Fermi pocket area via strain makes it possible to adjust the spin density wave critical interaction strength near the real one and enables a high superconducting critical temperature.
我们通过第一性原理计算研究了未掺杂双层硅烯的结构和物理性质,发现该体系本征为金属,具有可观的口袋费米面。当考虑真实的电子-电子相互作用时,该体系被确定为由反铁磁自旋密度波序边界上的强自旋涨落所介导的手性 d+id'拓扑超导体。此外,通过应变可调的费米口袋面积使得可以调整接近真实的自旋密度波临界相互作用强度,从而实现较高的超导临界温度。