拓扑超导材料和马约拉纳费米子的实验探究

The search for Majorana fermions in solid state system is one of paramount research targets in physics today. In this project, we would explore the molecular beam epitaxy growth of high quality single-component topological superconductors with controlled film thickness and chemical potential, establish the dynamical growth conditions, and then explore their exotic topologically nontrivial superconducting properties and long-sought Majorana fermions by in-situ low temperature scanning tunneling microscopy/spectroscopy under magnetic field. We aim to find the definitive evidence of Majorana zero modes, clarify the interactions between them as well as the mechanism of dissipative broadening, paving the material foundation for future topological quantum computation. The present study not only helps unambiguously confirm the existence of Majorana zero modes in real space, but also offers new wisdom and avenue for exploring simple topological superconductors.

在固体物质中寻找马约拉纳费米子态是当前物理学最重要的前沿课题之一。在本项目中，我们拟利用分子束外延技术探索制备多种高质量、厚度和化学势可控的单一拓扑超导薄膜材料，并建立其分子束外延生长的动力学条件，进而利用原位的低温强磁场扫描隧道显微镜/谱研究其新奇的拓扑超导性质和马约拉纳费米子态。我们预期通过这项工作获得马约拉纳费米子态存在的确切证据及其相互作用和耗散机理，为未来拓扑量子计算奠定重要的材料基础。开展此项目研究不仅可以在实空间确证马约拉纳费米子态的存在，而且也为探究简单拓扑超导材料提供了新的思路和实验途径。

探索新奇拓扑超导态及其承载的马约拉纳零能模是凝聚态物理研究领域的重要研究课题。本项目实施四年来，我们主要探索制备了多种二元合金、过渡金属硫族化合物和非常规高温超导薄膜，并对其表面结构、新奇超导性质和磁通涡旋中心的新奇零能峰进行了系统的研究，同时还开展了基于异质外延薄膜界面超导新体系以及高温超导微观机理方面的深入探究，取得了一系列重要的实验进展。该项目所建立的多种量子薄膜材料的分子束外延生长方法为后续研究提供重要的借鉴。