Bogoliubov分段费米面及该体系中马约拉纳零能模的STM研究

自BCS理论提出后，超电流和磁场对超导体中Bogoliubov准粒子的影响被认为是理解超导体特性的关键。理论预言在超电流作用下可以产生无能隙的超导态，即Bogoliubov准粒子形成的分段费米面。但是由于缺乏动量分辨，人们始终未能观测到该有趣的实验现象。本项目主要研究利用近邻效应在拓扑表面态中引入超导电性，通过表面敏感的扫描隧道显微镜技术，对Bogoliubov准粒子形成的分段费米面进行表征。以期通过极低温和矢量磁场下的准粒子干涉技术获得分段费米面的性质。此外，利用该分段费米面，通过外加量子限制，可以获得马约拉纳零能模。该马约拉纳零能模产生条件具有外加磁场小，无需调节化学势，排除其他低能激发态，大的拓扑能隙等优点，有望为构造拓扑量子比特，实现拓扑量子计算提供了一个新的体系。

The impact of supercurrents and external magnetic field on the behavior of Bogoliubov quasiparticles has been recognized as crucial in understanding the properties of superconductors since the very early days of Bardeen-Cooper-Schrieffer theory. Theoretical physicists have predicted that sufficiently large supercurrent can lead to a gapless superconducting state with segmented Fermi surface of Bogoliubov quasiparticles. However, due to the lack of momentum resolution, the novel phenomenon has never been directly observed. The project focuses on the research of proximitized topological surface states, and exhibit the segmented Fermi surface of Bogoliubov quasiparticles through scanning tunneling microscopy. We anticipate revealing the properties of the segmented Fermi surface via quasiparticle interference under ultra-low temperature and vector magnetic field. Besides, the Majorana zero mode may emerge by quantum confinement of the segmented Fermi surface. This setup has key advantages that include: small required fields, no necessity of fine-tuning of chemical potential, removal of the low-energy detrimental states, and large attainable topological gap. Meanwhile, it provides a new platform for the construction of topological qubit and the realization of topological quantum computation.