2020/02/29 by Shawulienu Kezilebieke, Md Nurul Huda, Viliam Vaňo +7 · 2 citations
Materials Science · Physics and Astronomy · #2D Materials and Applications #Graphene research and applications #Heterojunction #MAJORANA #Majorana fermion #Proximity effect (electron beam lithography) #Scanning tunneling microscope #Superconductivity #Topological Materials and Phenomena #Topological insulator #Topology (electrical circuits) #cond-mat.mes-hall #cond-mat.mtrl-sci #cond-mat.supr-con #van der Waals force
paper · pdf · doi:10.1038/s41586-020-2989-y
published as Nature 588, 424-428 (2020)
openalex created_date 2020/02/14 · openalex publication_date 2020/12/16 · arxiv created 2021/03/05 · arxiv updated 2021/03/08 · openalex updated_date 2026/08/05
The designer approach has become a new paradigm in accessing novel quantum phases of matter. Moreover, the realization of exotic states such as topological insulators, superconductors and quantum spin liquids often poses challenging or even contradictory demands for any single material. For example, it is presently unclear if topological superconductivity, which has been suggested as a key ingredient for topological quantum computing, exists at all in any naturally occurring material . This problem can be circumvented by using designer heterostructures combining different materials, where the desired physics emerges from the engineered interactions between the different components. Here, we employ the designer approach to demonstrate two major breakthroughs - the fabrication of van der Waals (vdW) heterostructures combining 2D ferromagnetism with superconductivity and the observation of 2D topological superconductivity. We use molecular-beam epitaxy (MBE) to grow two-dimensional islands of ferromagnetic chromium tribromide (CrBr3) on superconducting niobium diselenide (NbSe2) and show the signatures of one-dimensional Majorana edge modes using low-temperature scanning tunneling microscopy (STM) and spectroscopy (STS). The fabricated two-dimensional vdW heterostructure provides a high-quality controllable platform that can be integrated in device structures harnessing topological superconductivity. Finally, layered heterostructures can be readily accessed by a large variety of external stimuli potentially allowing external control of 2D topological superconductivity through electrical, mechanical, chemical, or optical means.