Nearly quantized conductance plateau of vortex zero mode in an iron-based superconductor

• DOI: 10.1126/science.aax0274
• Publication Date: 2019-12-13T00:09:13Z
• Authors: Shiyu Zhu; Lingyuan Kong; Lu Cao; Hui Chen; Michał Papaj; Shixuan Du; Yuqing Xing; Wenyao Liu; Dongfei Wang; Chengmin Shen; Fazhi Yang; John Schneeloch; Ruidan Zhong; Genda Gu; Liang Fu; Yu-Yang Zhang; Hong Ding; Hong-Jun Gao
• Keywords: Andreev reflection; Zero-point energy; Iron-based superconductor; Zero mode

Majorana zero-modes (MZMs) are spatially-localized zero-energy fractional quasiparticles with non-Abelian braiding statistics that hold a great promise for topological quantum computing. Due to its particle-antiparticle equivalence, an MZM exhibits robust resonant Andreev reflection and 2e2/h quantized conductance at low temperature. By utilizing variable-tunnel-coupled scanning tunneling spectroscopy, we study of vortex bound states on FeTe0.55Se0.45 superconductors. We report observations plateaus as function tunnel coupling values close or even reaching the conductance. In contrast, no such plateau behaviors were observed either finite energy Caroli-de Genne-Matricon in continuum electronic outside superconducting gap. This unique behavior zero-mode strongly supports existence MZMs this iron-based superconductor, which serves promising single-material platform relatively high