Majorana fermions and parafermions in topological insulators

拓扑绝缘体中的马约拉纳费米子和平费米子

• 批准号: 400711809
• 负责人: Professor Dr. Laurens W. Molenkamp
• 金额: --
• 依托单位: Department of Physics
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2018
• 资助国家: 德国
• 起止时间: 2017-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/400711809?language=en
• 关键词: Majorana; fermions; parafermions; topological; insulators

Topological insulators and topological superconductors constitute a new class of quantum materials with a gapped bulk spectrum and gapless surface states. Due to topology, the appearance of these surface states is remarkably robust against external perturbations.In this proposal, we want to discover feasible ways to identify and manipulate Majorana fermions and parafermions in topological insulator hybrid structures. Majorana fermions and parafermions are fractional excitations that appear as boundary states of topological superconductors. They are known to be building blocks for qubits of a topological quantum computer.The system we have identified as the most promising platform for this task is a bilayer quantum spin Hall insulator in proximity to an ordinary s-wave superconductor. In that nanostructure, we expect a complex interplay between helicity, intra- and inter-layer Coulomb interaction, disorder, and superconducting order. The Basel and Würzburg groups, involved in the project, nicely complement each other in terms of theoretical skills (Basel: quantum computing; Würzburg: quantum transport) and the experimental ability (at Würzburg) to actually implement this challenging system in the laboratory. We are therefore confident that we will develop innovative ideas to generate and control Majorana fermions and parafermions at will within this consortium.

拓扑绝缘体和拓扑超导体构成了一类具有带隙体谱和无间隙表面态的新型量子材料。由于拓扑结构的原因，这些表面态的出现对外部扰动具有显著的健壮性。在这个方案中，我们希望找到可行的方法来识别和操纵拓扑绝缘体混合结构中的Majorana费米子和副费米子。Majorana费米子和准费米子是作为拓扑超导体的边界态出现的分数激发。它们被认为是拓扑量子计算机量子比特的基石。我们认为最有希望完成这项任务的系统是一个双层量子自旋霍尔绝缘体，它靠近一个普通的S波超导体。在这种纳米结构中，我们预计螺旋度、层内和层间库仑相互作用、无序和超导有序之间存在复杂的相互作用。参与该项目的巴塞尔和维尔茨堡小组在理论技能(巴塞尔：量子计算；维尔茨堡：量子传输)和在实验室实际实施这一具有挑战性的系统的实验能力(维尔茨堡)方面实现了很好的互补。因此，我们相信，我们将提出创新的想法，在这个联合体内随意产生和控制马约拉纳费米子和准费米子。