Topological superconductivity has been sought in a variety of heterostructure systems, the interest being that a material displaying such a phenomenon could prove to be the ideal platform to support Majorana fermions, which in turn could be the basis for advanced qubit technologies. Recently, the high-T_c family of superconductors, FeTe_1−xSe_x, have been shown to exhibit the property of topological superconductivity and further, evidence has been found for the presence of Majorana fermions. We have studied the interplay of topology, magnetism, and superconductivity in the FeTe_1−xSe_x family using high-resolution laser-based photoemission. At the bulk superconducting transition, a gap opens at the chemical potential as expected. However, a second gap is observed to open at the Dirac point in the topological surface state. The associated mass acquisition in the topological state points to time-reversal symmetry breaking, probably associated with the formation of ferromagnetism in the surface layer. The presence of intrinsic ferromagnetism combined with strong spin–orbit coupling provides an ideal platform for a range of exotic topological phenomena.

已经在各种异质结构系统中寻求拓扑超导性，感兴趣的是显示这种现象的材料可能被证明是支持马约拉纳费米子的理想平台，而这反过来又可能成为先进量子比特技术的基础。最近，高T _c系列超导体FeTe _1−x Se _x已被证明具有拓扑超导特性，此外，还发现了马约拉纳费米子存在的证据。我们研究了 FeTe _{1− x} Se _{x中拓扑结构、磁性和超导性的相互作用}家庭使用基于高分辨率激光的光电发射。在体超导转变处，如预期的那样，在化学势处打开了一个间隙。然而，观察到第二个间隙在拓扑表面状态的狄拉克点处打开。拓扑状态中相关的质量获取指向时间反演对称性破坏，可能与表面层中铁磁性的形成有关。固有铁磁性的存在与强自旋轨道耦合相结合，为一系列奇异的拓扑现象提供了理想的平台。