Strain-induced nematic response of the CDW in Sr-doped BaNi2As2

ORAL

Abstract

Ba1-xSrxNi2As2 (BSNA) is a pnictide superconductor that exhibits several charge density wave (CDW) phases and a diverging nematic susceptibility observed in transport experiments under applied uniaxial strain. The nematic susceptibility was found to become strain hysteretic in the incommensurate CDW (I-CDW) phase, suggesting that nematicity and the I-CDW phase are coupled, which is surprising because the I-CDW phase does not break C4 symmetry. To explore this coupling, we performed an x-ray scattering study of the CDW phases in BSNA x=0.27 under applied uniaxial strain. We find a large nematic response in the CDW as well, detected as a breaking of the C4 symmetry induced by the applied strain field. Our results indicate that the CDW is strongly coupled to the nematic order parameter and may even be the driver of nematic phenomena in this material.

*X-ray work was supported by DOE grant DE-FG02-06ER46285. BSNA sample growth was supported by the NSF grant DMR1905891. P. A. and J. P. acknowledge the Gordon and Betty Moore Foundation EPiQS grants No. GBMF9452 and No. GBMF9071, respectively.

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Presenters

  • Thomas A Johnson

    • University of Illinois at Urbana-Champaign
    • University of Illinois

Authors

  • Thomas A Johnson

    • University of Illinois at Urbana-Champaign
    • University of Illinois

  • Sangjun Lee

    • Samsung Advanced Institute of Technology
    • University of Illinois at Urbana-Champaign

  • John C Collini

    • University of Maryland, College Park

  • Stella Sun

    • University of Illinois at Urbana-Champaign

  • Matteo Mitrano

    • Harvard University

  • Xuefei Guo

    • University of Illinois at Urbana-Champaign
    • University of Illinois at Urbana-Champai

  • Chris Eckberg

    • University of Maryland, College Park
    • University of California, Los Angeles
    • US Army Research Laboratory

  • Johnpierre Paglione

    • University of Maryland, College Park
    • Maryland Quantum Materials Center, University of Maryland, College Park, MD 20742, USA
    • Univ of Maryland-College Park

  • Eduardo H Fradkin

    • University of Illinois at Urbana-Champaign
    • University of Illinois

  • Peter Abbamonte

    • University of Illinois at Urbana-Champai
    • University of Illinois at Urbana-Champaign
    • University of Illinois