Chemical CeO2-Based Buffer Layers for Fe(Se,Te) Films

IEEE Transactions on Applied Superconductivity, vol. 32, pp. 1–5

Abstract

Among other Fe-based superconductors, Fe(Se,Te) is particularly interesting because of the low structural anisotropy, large upper critical fields, low field dependence of the critical current density and low toxicity. It can also be grown as an epitaxial film on a metallic oriented substrate, making the fabrication of a Fe-based coated conductor (CC) possible. Less strict requirements on the template microstructure allow for the design of a simplified design compared to REBCO CCs. This design requires a buffer layer to promote the oriented growth of the superconducting film and avoid diffusion from the metallic template. In this work, CeO2based buffer layers are prepared on single crystals via two chemical deposition techniques, metal organic decomposition (MOD) and polymer assisted deposition (PAD). With the design of a suitable thermal treatment, it is possible to obtain oriented buffers with large flat grains and low values of surface roughness. Fe(Se,Te) films are deposited on these templates via laser deposition, and excellent samples are obtained when a Fe(Se,Te) seed layer is used to favour chemical matching with the buffer: sharp superconducting transitions around 16 K and critical current densities exceeding 1 MA cm−2at 4.2 K in self-field are observed. These results are the demonstration of the feasibility of a Fe-based CC architecture, with all the relative advantages concerning process simplification and cost reduction.

Authors 17

1. Laura Piperno

   National Agency for New Technologies, Energy and Sustainable Economic Development · Superconducting and other Innovative Materials and Devices Institute · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

   SPIN, CNR, Genova, Italy

2. Angelo Vannozzi

   National Agency for New Technologies, Energy and Sustainable Economic Development · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

3. Valentina Pinto

   National Agency for New Technologies, Energy and Sustainable Economic Development · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

4. A. Augieri

   National Agency for New Technologies, Energy and Sustainable Economic Development · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

5. Achille Angrisani Armenio

   National Agency for New Technologies, Energy and Sustainable Economic Development · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

6. Francesco Rizzo

   National Agency for New Technologies, Energy and Sustainable Economic Development · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

7. Antonella Mancini

   National Agency for New Technologies, Energy and Sustainable Economic Development · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

8. A. Rufoloni

   National Agency for New Technologies, Energy and Sustainable Economic Development · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

9. G. Celentano

   National Agency for New Technologies, Energy and Sustainable Economic Development · ENEA Frascati Research Centre

   Affiliation as printed

   ENEA, Frascati Research Centre, Frascati, Italy

10. V. Braccini

    Superconducting and other Innovative Materials and Devices Institute

    Affiliation as printed

    SPIN, CNR, Genova, Italy

11. Matteo Cialone

    Superconducting and other Innovative Materials and Devices Institute

    Affiliation as printed

    SPIN, CNR, Genova, Italy

12. Michela Iebole

    University of Genoa

    Affiliation as printed

    Physics Department, University of Genova, Genova, Italy

13. Nicola Manca

    Superconducting and other Innovative Materials and Devices Institute

    Affiliation as printed

    SPIN, CNR, Genova, Italy

14. A. Martinelli

    Superconducting and other Innovative Materials and Devices Institute

    Affiliation as printed

    SPIN, CNR, Genova, Italy

15. Marina Putti

    University of Genoa

    Affiliation as printed

    Physics Department, University of Genova, Genova, Italy

16. Giovanni Sotgiu

    Roma Tre University

    Affiliation as printed

    Faculty of Engineering, Roma Tre University, Rome, Italy

17. Alexander Meledin Aachen Central Facility for Electron Microscopy

    RWTH Aachen University

    Affiliation as printed

    Central Facility for Electron Microscopy, RWTH Aachen University, Aachen, Germany