Phase separation between superconducting and nematic domains in Co-doped CaFe$_2$As$_2$ close to a first order phase transition

ORAL

Abstract

We use Atomic Force, Magnetic Force and Scanning Tunneling Microscopy (AFM, MFM and STM) to identify a phase separated state in strained Co substituted CaFe$_2$As$_2$. Each phase is equivalent to what is found at either side of the first order phase transition between antiferromagnetic orthorhombic and superconducting tetragonal phases found in unstrained samples when changing Co concentration. Having such alternating superconducting domains separated by normal conducting domains with sizes of order of the coherence length opens opportunities to build Josephson junction networks or vortex pinning arrays and suggests that first order quantum phase transitions lead to nanometric size phase separation under the influence of strain.

*Supported by the Spanish AEI/MINECO (FIS2014-54498-R, MDM-2014-0377), EU CA16218 and PNICTEYES 679080. Work done in Ames supported by BES-DOE. Ames Lab is operated for the DOE by Iowa State University, DE-AC02-07CH11358.

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Presenters

  • Hermann Suderow

    • Univ Autonoma de Madrid
    • Universidad Autonoma de Madrid

Authors

  • Anton Fente

    • Univ Autonoma de Madrid
    • Universidad Autonoma de Madrid

  • Alex Correa

    • Univ Autonoma de Madrid

  • A.E. Böhmer

    • Ames Lab
    • Physics, Ames lab

  • Andreas Kreyssig

    • Ames Laboratory, Iowa State University
    • Dept. of Physics and Astronomy, Ames Laboratory/Iowa State University
    • Iowa State University
    • Ames Laboratory and Iowa State University, Dept. of Physics and Astronomy
    • Dept. of Physics, Iowa State Univ
    • Ames Lab

  • Sergey Bud'ko

    • The Ames Laboratory
    • Iowa state university/Ames Laboratory
    • Iowa State University and Ames Laboratory
    • Iowa State University/Ames Laboratory
    • Iowa State University / Ames Laboratory
    • Ames Laboratory and Iowa State University, Dept. of Physics and Astronomy
    • Dept. of Physics, Iowa State Univ
    • Ames Lab
    • Ames Laboratory U.S. DOE and Department of Physics and Astronomy, Iowa State University
    • Ames Laboratory
    • Department of Physics and Astronomy, Ames Laboratory and Iowa State University

  • Paul Canfield

    • Ames Laboratory and Iowa State University
    • Ames Laboratory, Iowa State University
    • Department of Physics and Astronomy, Iowa State University
    • Dept. of Physics and Astronomy, Ames Laboratory/Iowa State University
    • Iowa state university/Ames Laboratory
    • Ames Laboratory and Iowa State Univ
    • Iowa State University and Ames Laboratory
    • Iowa State University/Ames Laboratory
    • Iowa State University
    • Iowa State University / Ames Laboratory
    • Dept. of Physics, Iowa State Univ
    • Ames Lab
    • Ames Laboratory U.S. DOE and Department of Physics and Astronomy, Iowa State University
    • Iowa State Univ
    • Ames Laboratory
    • Department of Physics and Astronomy, Ames Laboratory and Iowa State University

  • Federico Mompean

    • ICMM, CSIC

  • Mar Garcia

    • ICMM, CSIC

  • Carmen Munuera

    • ICMM, CSIC

  • Isabel Guillamon

    • Univ Autonoma de Madrid
    • Laboratorio de Bajas Temperaturas, Unidad Asociada UAM CSIC, Departamento de Física de la Materia Condensada, Instituto Nicolás Cabrera and Condensed Matter Physics Center (IF
    • Universidad Autonoma de Madrid

  • Hermann Suderow

    • Univ Autonoma de Madrid
    • Universidad Autonoma de Madrid