High Quality Fe1+yTe Synthesized by Chemical Vapor Deposition with Conspicuous Vortex Flow

• Published in: Advanced functional materials 2024-09, Vol.34 (37), p.n/a
• Main Authors: Lv, Lu, Hu, Lihong, Dong, Weikang, Duan, Jingyi, Wang, Ping, Li, Peiling, Qu, Fanming, Lu, Li, Ye, Zimeng, Zhao, Junhao, Li, Jiafang, Deng, Fang, Liu, Guangtong, Zhou, Jiadong, Gao, Yanfeng
• Format: Article
• Language: English
• Subjects: 2D materials; Chemical synthesis; Chemical vapor deposition; CVD; Electrons; Fe1+yTe crystals; Fluid dynamics; Fluid flow; Iron; Ising model; Magnetic properties; Photoelectrons; Raman spectroscopy; Scanning transmission electron microscopy; Spectrum analysis; Superconductivity; Superconductors; Three dimensional flow; Two dimensional flow; Two dimensional materials; vortex flow; Vortices; X ray photoelectron spectroscopy
• ISSN: 1616-301X; 1616-3028
• DOI: 10.1002/adfm.202401748

2D materials provide an ideal platform to explore novel superconducting behavior including Ising superconductivity, topological superconductivity and Majorana bound states in different 2D stoichiometric Ta‐, Nb‐, and Fe‐based crystals. However, tuning the element content in 2D compounds for regulating their superconductivity has not been realized. In this work, the synthesis of high quality Fe1+yTe with tunable Fe content by chemical vapor deposition (CVD) is reported. The quality and composition of Fe1+yTe are characterized by Raman spectroscopy, X‐ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM). The superconducting behavior of Fe1+yTe crystals with varying Fe contents is observed. The superconducting transition of selected Fe1.13±0.06Te sample is sharp (ΔTc = 1 K), while Fe1.43±0.07Te with a high‐Fe content shows a relative broad superconducting transition (ΔTc = 2.6 K) at zero magnetic field. Significantly, the conspicuous vortex flow and a transition from a 3D vortex liquid state to a 2D vortex liquid state is observed in Fe1.43±0.07Te sample. This work highlights the tunability of the superconducting properties of Fe1+yTe and sheds light on the vortex dynamics in Fe‐based superconductors, which facilitates them to understand the intrinsic mechanisms of high‐temperature superconductivity. In this work, the controllable synthesis of 2D Fe1+yTe nanoflakes are realized with tunable Fe content by CVD method. Among them, the Fe1.13±0.06Te crystal exhibits a sharp superconducting transition (ΔTc = 1 K) at B = 0 T, and the transition temperature Tc is measured to be 10.2 K at B = 12 T. Additionally, the high‐Fe content Fe1.43±0.07Te crystal shows a relative broad superconducting transition (ΔTc = 2.6 K) at B = 0 T, and Tc is suppressed to 3.8 K at B = 12 T, which is related to the 3D‐to‐2D vortex liquid transition. This research will pave the way for understanding the intrinsic mechanisms of high‐temperature superconductivity.