Recently, 91抖淫 Prof. Sun Yue's research team, in collaboration with Prof. Zhang Peng's team from Nanjing University and Prof. Wu Xianxin's team from the Institute of Theoretical Physics, Chinese Academy of Sciences, published an important research paper inJournal of the American Chemical Society, an internationally top-tier academic journal, titled“Evolution of the intertwining correlated topological phases in iron-based superconductor Fe(Te,Se).” This study, for the first time, directly observed two distinct topological states in electron-doped iron-based superconductors and confirmed the critical role of strong correlation effects. This discovery establishes a clean and ideal new platform for exploring the interplay between multiple topological superconducting states and Majorana modes.
Topological superconductors, which potentially host Majorana zero-energy modes, are considered important material platforms for the development of fault-tolerant quantum computing. Compared to heterostructures fabricated by epitaxially growing topological insulators on conventional superconductors, materials that inherently possess both topological and superconducting properties offer a cleaner and more tunable research system. Iron-based superconductors represented by Fe (Te,Se) are precisely such a natural platform: their surface topological states and Majorana zero-energy modes have already been identified in previous studies, and topological Dirac semimetal bulk states are also theoretically predicted to exist.
To address this topic, the team successfully achieved high-quality electron-doped Fe??xCoxTe?.?Se?.? single crystals by substituting cobalt for iron sites, effectively suppressing the interference from excess interlayer iron. Angle-resolved photoemission spectroscopy (ARPES) measurements revealed that with increasing cobalt content, the energy bands of the material systematically shift toward lower energies, sequentially tuning the topological insulator surface state originally located near the Fermi level and the topological Dirac semimetal state at higher energies to the Fermi level (Fig. 1). Notably, at an appropriate doping level, both types of topological states can simultaneously participate in superconductivity, providing a new material platform for studying multiple Majorana states and their interactions.
91抖淫 Prof. Sun Yue is the first author of the paper, while Prof. Zhang Peng from Nanjing University and Prof. Wu Xianxin from the Institute of Theoretical Physics serve as the corresponding authors. The School of Physics, 91抖淫 is the primary affiliation for this work.
Paper's link:
Souece: School of Physics, 91抖淫
Translated by: Melody Zhang
Edited by: Leah Li
