Comparative study of Fe(Se, Te) thin films on flexible coated conductor templates and single-crystal substrates. (5th October 2021)

• Record Type: Journal Article
• Authors: Anna Thomas, Aleena; Shipulin, Ilya A; Holleis, Sigrid; Eisterer, Michael; Nielsch, Kornelius; Hühne, Ruben
• Is Part Of: Superconductor science & technology. Volume 34:Number 11(2021)
• Publication Date: 2021-10-05
• Subjects: thin films -- superconductor -- coated conductor -- Fe(Se, Te) -- epitaxy; Superconductivity -- Periodicals; Superconductors -- Periodicals; 537.623
• DOI: 10.1088/1361-6668/ac2557
• Languages: English
• ISSNs: 0953-2048

Abstract

Abstract: In this paper, we compare epitaxial Fe(Se, Te) thin films grown by pulsed laser deposition on CaF2, SrTiO3, MgO single crystals as well as on different metallic templates having a CeO2 based top surface. In particular, we performed a detailed structural and superconducting analysis. X-ray diffraction studies showed highly textured films on all templates. The superconducting transition temperatures are between 21 K and 14 K for Fe(Se, Te) films on CaF2 and on MgO single-crystal substrates, respectively, whereas films on the metal templates show T c values up to 18 K. The critical current density ( J c ) was determined from magnetization loops in fields up to 7 T. Calculations in the framework of the extended critical state model showed J c values over 2 MA cm −2 and 0.9 MA cm −2 at 5 K in self-field on single-crystal substrates and metal templates substrates, respectively. Detailed transmission electron microscopy studies reveal smooth layers on all templates. Whereas small defects were found in films on single crystals, pronounced grain boundaries with higher misorientation angle were visible in the layers on metallic templates.