High-field Magnetization Response as Evidence for Dominant Ferromagnetic Kitaev Correlations in the Alkali Iridate Na<sub>2</sub>IrO<sub>3</sub>

ORAL

Abstract


The alkali Iridate Na2IrO3 has received much attention, theoretically and experimentally, as a prime candidate for realizing Kitaev physics. Despite the progress made, the sign of the dominant Kitaev interaction remains an open question. The high field magnetization response is a potentially important tool for addressing this question. In this talk, I will discuss the experimentally observed magnetization response of Na2IrO3 for magnetic fields up to 60 Tesla, with a robust peak-dip feature at fields corresponding to the zigzag ordering ( ≈ 15K) temperature. This will be compared with the torque response obtained from numerical exact diagonalization of the well-known models used to describe Na2IrO3, thus constraining the effective spin models to those with a dominant ferromagnetic Kitaev and subdominant antiferromagnetic Heisenberg exchange, accompanied by smaller competing interactions. I will further discuss the nature of the spin correlation function, found to decay rapidly at high fields, akin to a quantum spin liquid state.

*DST(Grant No. DST/SJF/PSA-0212012-13), the Royal Society, the Winton Programme, ERC(FP7 (grant number FP/2007-2013)/ERC Grant AGMT no. 337425), DOE-BES(DE-SC0002613), NSF(grant DMR 1712101), HFML-RU/FOM, NSERC and CQM, UofT

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Presenters

  • Sarbajaya Kundu

    • Department of Theoretical Physics, Tata Institute of Fundamental Research

Authors

  • Sarbajaya Kundu

    • Department of Theoretical Physics, Tata Institute of Fundamental Research

  • Sitikantha Das

    • Department of Physics, IIT Kharagpur

  • Zengwei Zhu

    • Wuhan National High Magnetic Field Center
    • Wuhan National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology
    • National High Magnetic Field Center and School of Physics, Huazhong University of Science and Technology

  • Eundeok Mun

    • Physics, Simon Fraser University
    • Department of Physics, Simon Fraser University

  • Ross McDonald

    • Los Alamos National Laboratory
    • National High Magnetic Field Laboratory
    • Pulsed Field Facility, Los Alamos National Lab
    • Los Alamos Natl Lab
    • LANL/NHMFL
    • NHMFL-PFF, Los Alamos National Laboratory
    • National High Magnetic Field Laboratory, LANL

  • Gang Li

    • Institute of Physics, Chinese Academy of Sciences

  • Luis Balicas

    • Natl High Magnetic Field Lab
    • Nat. High Magn. Field Lab., Florida State University
    • FSU-NHMFL
    • National High Magnetic Field Lab
    • National High Magnetic Field Laboratory
    • Natl. High Magnetic Field Lab, Florida State University
    • High Field Magnet Lab
    • 1800 E. Paul Dirac Drive, National High Magnetic Field Laboratory, Natl High Magnetic Field Lab

  • Alix McCollam

    • High Field Magnet Laboratory , Radboud University
    • High Field Magnet Laboratory, Radboud University

  • Gang Cao

    • Physics, Univ of Colorado - Boulder
    • Department of Physics, University of Colorado-Boulder
    • Department of Physics, University of Colorado Boulder
    • Materials Science and Engineering Program, University of Colorado Boulder
    • Department of Physics, Univ of Colorado - Boulder
    • Department of Physics, University of Colorado
    • University of Colorado at Boulder

  • Jeffrey Rau

    • Department of Physics and Astronomy, University of Waterloo

  • Hae-Young Kee

    • Physics, University of Toronto
    • Department of Physics, University of Toronto
    • University of Toronto
    • Physics, Univ of Toronto

  • Vikram Tripathi

    • Department of Theoretical Physics, Tata Institute of Fundamental Research

  • Suchitra Sebastian

    • Cavendish Laboratory, Univ of Cambridge
    • Univ of Cambridge
    • Cavendish Laboratory, University of Cambridge