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Pressure-evolution of a symmetry-broken <i>S</i> = ½ dimer magnet

ORAL

Abstract

A lattice of weakly interacting, antiferromagnetically coupled spin-half dimers can be well described within a Bose-Einstein condensate (BEC) of magnons model, provided the rotational symmetry of the spin Hamiltonian is preserved. The material CuVOF4(H2O)6H2O, appears to exhibit behaviour typical of a dimer system, with electron-spin resonance and magnetometry data confirming the field-induced closing of an energy-gap between the excited triplet-state and singlet ground-state energy levels. However, as the dimer-unit is composed of two unlike spin-half ions, Cu(II) and V(IV), we are presented with the interesting situation where the rotational symmetry of the system is broken by the spins in the dimer-units themselves. Here we discuss the unusual hydrogen-bond-mediated exchange pathways in this material and the resultant phase diagram. In addition, we show that the application of hydrostatic pressure serves to tune the magnitude of the intradimer exchange interaction, as well as push the system through a structural phase-transition at pressures beyond 20 kbar.

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Presenters

  • Sam Curley

    Department of Physics, University of Warwick

Authors

  • Sam Curley

    Department of Physics, University of Warwick

  • Matthew J Coak

    Department of Physics, University of Warwick, University of Warwick, Univ of Warwick

  • Robert C Williams

    Department of Physics, University of Warwick

  • Saman Ghannadzadeh

    Department of Physics, University of Oxford

  • Dmytro Kamenskyi

    University of Augsburg

  • Andreas Schneider

    University of Augsburg

  • Susumo Okubo

    Kobe University

  • Takahiro Sakurai

    Kobe University

  • Hitoshi Ohta

    Kobe University

  • Benjamin Michael Huddart

    Department of Physics, Durham University, Department of Physics, University of Durham

  • Tom Lancaster

    Department of Physics, Durham University, Department of Physics, University of Durham

  • David E Graf

    National High Magnetic Field Laboratory, Florida State University, National High Magnetic Field Lab, Florida State University, National High Magnetic Field Laboratory, Tallahassee and Florida State University, National High Magnetic Field Laboratory, Florida State University, National High Magnetic Field Laboratory (FSU), Department of Physics, Florida State University, National High Magnetic Field Laboratory and Department of Physics, Florida State University, National High Magnetic Field Lab, National High Magnetic Field Laboratory, Tallahassee, FL, CMS, National High Magnetic Laboratory

  • Jere Tidy

    Department of Chemistry, University of Warwick

  • Mark Senn

    Department of Chemistry, University of Warwick, Chemistry, University of Warwick

  • Jamie L Manson

    Department of Chemistry and Biochemistry, Eastern Washington University, Eastern Washington University

  • Paul Goddard

    Department of Physics, University of Warwick, University of Warwick, Physics, University of Warwick