Breakdown of magnetic order in the pressurized 3D Kitaev iridate β-Li2IrO3

ORAL

Abstract

Novel electronic and magnetic properties are found in honeycomb lattice iridates, having dominant Kitaev interactions, due to the presence of strong spin-orbit coupling and electronic correlations. We present the measurements of magnetization, thermal expansion, magnetostriction, muon spin resonance, single crystal x-ray diffraction under hydrostatic pressure of 3D hyperhoneycomb β-Li2IrO3. These measurements are complemented by the ab initio calculations. The incommensurate magnetic order at 38 K initially increases as a function of hydrostatic pressure with a rate of 0.9 K/ GPa, consistent with the thermodynamic Ehrenfest relation. The partial polarization at 2.5 T decreases with increasing pressure signifies the instability of the magnetic order. The ordered state breaks down upon a first-order transition at around 1.4 GPa, giving way to a new ground state marked by the coexistence of dynamically correlated and frozen spins. This partial spin freezing may indicate the classical nature of the resulting pressure-induced spin-liquid, expected for large-Γ (nearest-neighbor off-diagonal exchange) limit [1].
[1] M. M., R. S. Manna et al., Phys. Rev. Lett. 120, 237202 (2018).

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Presenters

  • Rudra Sekhar Manna

    Department of Physics, Indian Institute of Technology Tirupati, Renigunta Road, Settipalli post, Tirupati - 517506, AP, India

Authors

  • Rudra Sekhar Manna

    Department of Physics, Indian Institute of Technology Tirupati, Renigunta Road, Settipalli post, Tirupati - 517506, AP, India

  • M Majumder

    EP VI, EKM, University of Augsburg, 86159 Augsburg, Germany

  • G. Simutis

    PSI, 5232 Villigen, Switzerland

  • Orain Jean Christophe

    Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, PSI, 5232 Villigen, Switzerland

  • T. Dey

    EP VI, EKM, University of Augsburg, 86159 Augsburg, Germany

  • F. Freund

    EP VI, EKM, University of Augsburg, 86159 Augsburg, Germany

  • Anton Jesche

    EP VI, EKM, University of Augsburg, 86159 Augsburg, Germany

  • Rustem Khasanov

    Laboratory for Muon Spin Spectroscopy, Paul Scherrer Institute, Paul Scherrer Institut, Paul Scherrer Institute, Paul Sherrer Institut, PSI, 5232 Villigen, Switzerland

  • P. K. Biswas

    ISIS Pulsed Neutron and Muon Source, STFC Rutherford Appleton Laboratory, ISIS Neutron and Muon Sources, Science & Technology Facilities Council, ISIS Facility, Science and Technology Facilities Council Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Chilton, Didcot OX11 0QX, UK., ISIS, STFC Rutherford Appleton Laboratory, Didcot, Oxfordshire OX11 0QX, UK

  • E. Bykova

    Laboratory of Crystallography, University of Bayreuth, 95440 Bayreuth, Germany

  • Natalia Dubrovinskaia

    University of Bayreuth, Material Physics and Technology at Extreme Conditions, Laboratory of Crystallography, University of Bayreuth, Laboratory of Crystallography, University of Bayreuth, 95440 Bayreuth, Germany

  • L. S. Dubrovinsky

    Bavarian Geoinstitute, Bayreuth Univeristy, Bayerisches Geoinstitut, University of Bayreuth, 95440 Bayreuth, Germany

  • R. Yadav

    Institute for Theoretical Physics, IFW Dresden, 01069 Dresden, Germany

  • L. Hozoi

    IFW Dresden, Institute for Theoretical Physics, IFW Dresden, 01069 Dresden, Germany

  • S. Nishimoto

    Institute for Theoretical Solid State Physics, IFW Dresden, Institute for Theoretical Physics, IFW Dresden, 01069 Dresden, Germany

  • Alexander Tsirlin

    University of Augsburg, EP VI, EKM, University of Augsburg, 86159 Augsburg, Germany

  • Philipp Gegenwart

    EP VI, EKM, University of Augsburg, 86159 Augsburg, Germany